| 0001.Two Sum |
Easy (52.31%) |
array, hash-table, sort |
cpp, rust |
| 0002.Add Two Numbers |
Medium (42.66%) |
linked-list, arithmetic |
cpp |
| 0003.Longest Substring Without Repeating Characters |
Medium (34.70%) |
hash-table, sliding-window |
cpp |
| 0004.Median of Two Sorted Arrays |
Hard (39.79%) |
array, binary-search, divide-and-conquer |
cpp |
| 0005.Longest Palindromic Substring |
Medium (33.77%) |
string, dynamic-programming, palindrome |
cpp |
| 0006.Zigzag Conversion |
Medium (47.76%) |
string |
cpp |
| 0007.Reverse Integer |
Medium (28.52%) |
math |
cpp |
| 0008.String to Integer (atoi) |
Medium (17.18%) |
math, string |
cpp |
| 0009.Palindrome Number |
Easy (56.14%) |
math, palindrome |
cpp |
| 0010.Regular Expression Matching |
Hard (28.14%) |
dynamic-programming, backtracking, string |
cpp |
| 0011.Container With Most Water |
Medium (55.13%) |
array, two-pointers |
cpp |
| 0012.Integer to Roman |
Medium (64.59%) |
greedy |
cpp |
| 0013.Roman to Integer |
Easy (61.05%) |
hash-table, string |
cpp |
| 0014.Longest Common Prefix |
Easy (42.67%) |
string, sort |
cpp |
| 0015.3Sum |
Medium (34.41%) |
array, two-pointers, sorting, target-sum |
cpp |
| 0016.3Sum Closest |
Medium (45.79%) |
array, two-pointers, sorting, target-sum |
cpp |
| 0017.Letter Combinations of a Phone Number |
Medium (60.27%) |
string, backtracking, depth-first-search, breadth-first-search, recursion |
cpp |
| 0018.4Sum |
Medium (36.23%) |
array, two-pointers, target-sum |
cpp |
| 0019.Remove Nth Node From End of List |
Medium (45.15%) |
linked-list, fast-slow-pointers |
cpp |
| 0020.Valid Parentheses |
Easy (40.54%) |
string, stack |
cpp |
| 0021.Merge Two Sorted Lists |
Easy (64.18%) |
linked-list |
cpp |
| 0022.Generate Parentheses |
Medium (74.44%) |
string, backtracking, parentheses |
cpp |
| 0023.Merge k Sorted Lists |
Hard (52.59%) |
linked-list, heap |
cpp |
| 0024.Swap Nodes in Pairs |
Medium (64.24%) |
linked-list, recursion |
cpp |
| 0025.Reverse Nodes in k-Group |
Hard (58.47%) |
linked-list |
cpp |
| 0026.Remove Duplicates from Sorted Array |
Easy (55.42%) |
array, two-pointers, in-place-algorithm |
cpp |
| 0027.Remove Element |
Easy (56.58%) |
array, two-pointers, in-place-algorithm |
cpp |
| 0028.Find the Index of the First Occurrence in a String |
Easy (42.16%) |
string |
|
| 0029.Divide Two Integers |
Medium (17.43%) |
math, arithmetic, bit-manipulation |
cpp |
| 0030.Substring with Concatenation of All Words |
Hard (32.51%) |
hash-table, sliding-window, string |
cpp |
| 0031.Next Permutation |
Medium (39.77%) |
array, permutation |
cpp |
| 0032.Longest Valid Parentheses |
Hard (34.08%) |
string, dynamic-programming, stack, parentheses, subarray |
cpp |
| 0033.Search in Rotated Sorted Array |
Medium (40.66%) |
array, binary-search, search-in-rotated-sorted-array |
cpp |
| 0034.Find First and Last Position of Element in Sorted Array |
Medium (44.19%) |
array, binary-search |
cpp |
| 0035.Search Insert Position |
Easy (45.77%) |
array, binary-search |
cpp |
| 0036.Valid Sudoku |
Medium (59.55%) |
hash-table, bit-manipulation |
cpp |
| 0037.Sudoku Solver |
Hard (60.92%) |
hash-table, backtracking, bit-manipulation |
cpp |
| 0038.Count and Say |
Medium (54.89%) |
string, recursion |
cpp |
| 0039.Combination Sum |
Medium (71.28%) |
sort, backtracking, combination |
cpp |
| 0040.Combination Sum II |
Medium (54.43%) |
array, backtracking, sort, combination |
cpp |
| 0041.First Missing Positive |
Hard (39.42%) |
array |
cpp |
| 0042.Trapping Rain Water |
Hard (61.04%) |
array, two-pointers, monotonic-stack, stack |
cpp |
| 0043.Multiply Strings |
Medium (40.29%) |
string, arithmetic |
cpp |
| 0044.Wildcard Matching |
Hard (27.85%) |
dynamic-programming, backtracking, string |
cpp |
| 0045.Jump Game II |
Medium (40.41%) |
array, greedy |
cpp |
| 0046.Permutations |
Medium (78.23%) |
depth-first-search, backtracking |
cpp |
| 0047.Permutations II |
Medium (59.09%) |
depth-first-search, backtracking, hash-table |
cpp |
| 0048.Rotate Image |
Medium (74.15%) |
array, matrix |
cpp |
| 0049.Group Anagrams |
Medium (68.43%) |
hash-table, string, sort |
cpp |
| 0050.Pow(x, n) |
Medium (34.70%) |
math, divide-and-conquer, bit-manipulation |
cpp |
| 0051.N-Queens |
Hard (67.99%) |
backtracking |
cpp |
| 0052.N-Queens II |
Hard (73.76%) |
backtracking |
cpp |
| 0053.Maximum Subarray |
Medium (50.72%) |
divide-and-conquer, dynamic-programming, array, subarray |
cpp |
| 0054.Spiral Matrix |
Medium (49.28%) |
matrix, array |
cpp |
| 0055.Jump Game |
Medium (38.50%) |
array, greedy |
cpp |
| 0056.Merge Intervals |
Medium (47.24%) |
sort, interval |
cpp |
| 0057.Insert Interval |
Medium (41.42%) |
sort, interval, array |
cpp |
| 0058.Length of Last Word |
Easy (51.26%) |
string, two-pointers |
cpp |
| 0059.Spiral Matrix II |
Medium (70.98%) |
array, matrix |
cpp |
| 0060.Permutation Sequence |
Hard (46.75%) |
math, permutation |
cpp |
| 0061.Rotate List |
Medium (37.64%) |
linked-list, fast-slow-pointers |
cpp |
| 0062.Unique Paths |
Medium (64.23%) |
dynamic-programming, math |
cpp |
| 0063.Unique Paths II |
Medium (41.49%) |
dynamic-programming |
cpp |
| 0064.Minimum Path Sum |
Medium (63.76%) |
dynamic-programming |
cpp |
| 0065.Valid Number |
Hard (19.72%) |
string, finite-automata |
cpp |
| 0066.Plus One |
Easy (45.16%) |
array |
cpp |
| 0067.Add Binary |
Easy (53.45%) |
string, math |
cpp |
| 0068.Text Justification |
Hard (43.18%) |
string, greedy |
cpp |
| 0069.Sqrt(x) |
Easy (38.68%) |
math, binary-search |
cpp |
| 0070.Climbing Stairs |
Easy (52.85%) |
dynamic-programming, fibonacci-number |
cpp |
| 0071.Simplify Path |
Medium (42.23%) |
string, stack |
cpp |
| 0072.Edit Distance |
Medium (56.31%) |
string, dynamic-programming |
cpp |
| 0073.Set Matrix Zeroes |
Medium (55.42%) |
array |
cpp |
| 0074.Search a 2D Matrix |
Medium (50.00%) |
matrix, binary-search |
cpp |
| 0075.Sort Colors |
Medium (62.07%) |
array, two-pointers, sort |
cpp |
| 0076.Minimum Window Substring |
Hard (42.90%) |
hash-table, sliding-window, string |
cpp |
| 0077.Combinations |
Medium (70.28%) |
backtracking, divide-and-conquer, combination |
cpp |
| 0078.Subsets |
Medium (77.35%) |
array, backtracking, bit-manipulation, subset |
cpp |
| 0079.Word Search |
Medium (42.66%) |
matrix, backtracking, depth-first-search |
cpp |
| 0080.Remove Duplicates from Sorted Array II |
Medium (57.95%) |
in-place algorithm, array |
cpp |
| 0081.Search in Rotated Sorted Array II |
Medium (37.62%) |
array, binary-search, search-in-rotated-sorted-array |
cpp |
| 0082.Remove Duplicates from Sorted List II |
Medium (47.34%) |
linked-list |
cpp |
| 0083.Remove Duplicates from Sorted List |
Easy (52.41%) |
linked-list, duplicate |
cpp |
| 0084.Largest Rectangle in Histogram |
Hard (44.23%) |
monotonic-stack, array |
cpp |
| 0085.Maximal Rectangle |
Hard (47.03%) |
matrix, stack, monotonic-stack |
cpp |
| 0086.Partition List |
Medium (56.17%) |
linked-list |
cpp |
| 0087.Scramble String |
Hard (40.03%) |
string, dynamic-programming, memoization |
cpp |
| 0088.Merge Sorted Array |
Easy (49.48%) |
array, two-pointers |
cpp |
| 0089.Gray Code |
Medium (59.07%) |
hash-table, backtracking, bit-manipulation |
cpp |
| 0090.Subsets II |
Medium (57.18%) |
array, backtracking, bit-manipulation |
cpp |
| 0091.Decode Ways |
Medium (34.81%) |
string, dynamic-programming |
cpp |
| 0092.Reverse Linked List II |
Medium (47.62%) |
linked-list |
cpp |
| 0093.Restore IP Addresses |
Medium (49.73%) |
string, backtracking, depth-first-search |
cpp |
| 0094.Binary Tree Inorder Traversal |
Easy (76.01%) |
stack, binary-tree |
cpp |
| 0095.Unique Binary Search Trees II |
Medium (57.62%) |
recursion, binary-search-tree, binary-tree |
cpp |
| 0096.Unique Binary Search Trees |
Medium (60.96%) |
dynamic-programming, binary-search-tree, binary-tree, math |
cpp |
| 0097.Interleaving String |
Medium (39.89%) |
string, dynamic-programming, depth-first-search, memoization, hash-table |
cpp |
| 0098.Validate Binary Search Tree |
Medium (32.87%) |
binary-search-tree, binary-tree |
cpp |
| 0099.Recover Binary Search Tree |
Medium (53.00%) |
binary-search-tree, binary-tree, depth-first-search, sort |
cpp |
| 0100.Same Tree |
Easy (61.96%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0101.Symmetric Tree |
Easy (56.37%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0102.Binary Tree Level Order Traversal |
Medium (67.05%) |
binary-tree, breadth-first-search |
cpp |
| 0103.Binary Tree Zigzag Level Order Traversal |
Medium (58.84%) |
binary-tree, breadth-first-search |
cpp |
| 0104.Maximum Depth of Binary Tree |
Easy (75.27%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0105.Construct Binary Tree from Preorder and Inorder Traversal |
Medium (63.76%) |
binary-tree, hash-table |
cpp |
| 0106.Construct Binary Tree from Inorder and Postorder Traversal |
Medium (62.67%) |
binary-tree, hash-table |
cpp |
| 0107.Binary Tree Level Order Traversal II |
Medium (63.28%) |
binary-tree, breadth-first-search, depth-first-search |
cpp |
| 0108.Convert Sorted Array to Binary Search Tree |
Easy (71.58%) |
binary-tree, array, depth-first-search |
cpp |
| 0109.Convert Sorted List to Binary Search Tree |
Medium (61.80%) |
linked-list, binary-search-tree, fast-slow-pointers |
cpp |
| 0110.Balanced Binary Tree |
Easy (51.90%) |
binary-tree, depth-first-search |
cpp |
| 0111.Minimum Depth of Binary Tree |
Easy (47.76%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0112.Path Sum |
Easy (50.24%) |
binary-tree, path-sum |
cpp |
| 0113.Path Sum II |
Medium (58.38%) |
binary-tree, path-sum |
cpp |
| 0114.Flatten Binary Tree to Linked List |
Medium (64.76%) |
binary-tree, depth-first-search, linked-list |
cpp |
| 0115.Distinct Subsequences |
Hard (46.77%) |
dynamic-programming, string |
cpp |
| 0116.Populating Next Right Pointers in Each Node |
Medium (62.56%) |
binary-tree |
cpp |
| 0117.Populating Next Right Pointers in Each Node II |
Medium (52.37%) |
binary-tree |
cpp |
| 0118.Pascal's Triangle |
Easy (74.11%) |
array |
cpp |
| 0119.Pascal's Triangle II |
Easy (63.90%) |
array, math |
cpp |
| 0120.Triangle |
Medium (56.45%) |
dynamic-programming |
cpp |
| 0121.Best Time to Buy and Sell Stock |
Easy (53.60%) |
array, best-time-to-buy-and-sell-stock |
cpp |
| 0122.Best Time to Buy and Sell Stock II |
Medium (66.32%) |
array, greedy, best-time-to-buy-and-sell-stock |
cpp |
| 0123.Best Time to Buy and Sell Stock III |
Hard (47.84%) |
array, greedy, dynamic-programming, best-time-to-buy-and-sell-stock |
cpp |
| 0124.Binary Tree Maximum Path Sum |
Hard (39.99%) |
binary-tree, depth-first-search |
cpp |
| 0125.Valid Palindrome |
Easy (47.30%) |
string, two-pointers |
cpp |
| 0126.Word Ladder II |
Hard (27.29%) |
string, backtracking, breadth-first-search, depth-first-search |
cpp |
| 0127.Word Ladder |
Hard (39.04%) |
breadth-first-search, hash-table |
cpp |
| 0128.Longest Consecutive Sequence |
Medium (47.29%) |
array, hash-table, sort |
cpp |
| 0129.Sum Root to Leaf Numbers |
Medium (63.68%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0130.Surrounded Regions |
Medium (39.26%) |
depth-first-search, breadth-first-search, union-find, matrix |
cpp |
| 0131.Palindrome Partitioning |
Medium (67.41%) |
depth-first-search, backtracking, palindrome |
cpp |
| 0132.Palindrome Partitioning II |
Hard (33.89%) |
dynamic-programming, palindrome, string |
cpp |
| 0133.Clone Graph |
Medium (57.06%) |
hash-table, depth-first-search, breadth-first-search, graph, deep-copy |
cpp |
| 0134.Gas Station |
Medium (45.52%) |
greedy, math |
cpp |
| 0135.Candy |
Hard (43.27%) |
array, greedy |
cpp |
| 0136.Single Number |
Easy (72.74%) |
bit-manipulation |
cpp |
| 0137.Single Number II |
Medium (62.51%) |
bit-manipulation |
cpp |
| 0138.Copy List with Random Pointer |
Medium (55.92%) |
linked-list, hash-table, design, deep-copy |
cpp |
| 0139.Word Break |
Medium (46.72%) |
dynamic-programming, hash-table, string |
cpp |
| 0140.Word Break II |
Hard (47.85%) |
depth-first-search, memorization |
cpp |
| 0141.Linked List Cycle |
Easy (50.31%) |
linked-list, two-pointers, hash-table, fast-slow-pointers |
cpp |
| 0142.Linked List Cycle II |
Medium (51.17%) |
linked-list, fast-slow-pointers |
cpp |
| 0143.Reorder List |
Medium (58.51%) |
linked-list, fast-slow-pointers, stack |
cpp |
| 0144.Binary Tree Preorder Traversal |
Easy (69.37%) |
binary-tree, stack |
cpp |
| 0145.Binary Tree Postorder Traversal |
Easy (70.78%) |
binary-tree |
cpp |
| 0146.LRU Cache |
Medium (42.38%) |
design |
cpp |
| 0147.Insertion Sort List |
Medium (53.40%) |
sort, linked-list |
cpp |
| 0148.Sort List |
Medium (57.73%) |
linked-list, merge-sort |
cpp |
| 0149.Max Points on a Line |
Hard (26.62%) |
hash-table, math, geometry |
cpp |
| 0150.Evaluate Reverse Polish Notation |
Medium (51.26%) |
stack |
cpp |
| 0151.Reverse Words in a String |
Medium (41.82%) |
string, two-pointers |
cpp |
| 0152.Maximum Product Subarray |
Medium (35.03%) |
array, dynamic-programming |
cpp |
| 0153.Find Minimum in Rotated Sorted Array |
Medium (50.26%) |
array, binary-search, search-in-rotated-sorted-array, divide-and-conquer |
cpp |
| 0154.Find Minimum in Rotated Sorted Array II |
Hard (43.66%) |
array, binary-search, search-in-rotated-sorted-array, divide-and-conquer |
cpp |
| 0155.Min Stack |
Medium (54.05%) |
stack, design |
cpp |
| 0156.Binary Tree Upside Down 🔒 |
Medium (62.71%) |
binary-tree |
cpp |
| 0157.Read N Characters Given Read4 🔒 |
Easy (41.47%) |
string, design |
cpp |
| 0158.Read N Characters Given read4 II - Call Multiple Times 🔒 |
Hard (42.23%) |
string, design |
cpp |
| 0159.Longest Substring with At Most Two Distinct Characters 🔒 |
Medium (55.30%) |
sliding-window, hash-table, string |
cpp |
| 0160.Intersection of Two Linked Lists |
Easy (57.30%) |
linked-list, two-pointers |
cpp |
| 0161.One Edit Distance 🔒 |
Medium (34.28%) |
string |
cpp |
| 0162.Find Peak Element |
Medium (45.93%) |
array, binary-search |
cpp |
| 0163.Missing Ranges 🔒 |
Easy (33.58%) |
array, interval |
cpp |
| 0164.Maximum Gap |
Medium (45.79%) |
sort, bucket-sort, array |
cpp |
| 0165.Compare Version Numbers |
Medium (36.83%) |
string, two-pointers |
cpp |
| 0166.Fraction to Recurring Decimal |
Medium (24.97%) |
hash-table, arithmetic |
cpp |
| 0167.Two Sum II - Input Array Is Sorted |
Medium (61.16%) |
array, two-pointers, binary-search |
cpp |
| 0168.Excel Sheet Column Title |
Easy (40.54%) |
math, string, easy |
cpp |
| 0169.Majority Element |
Easy (64.78%) |
sort, array, bit-manipulation, boyer-moore-voting-algorithm |
cpp |
| 0170.Two Sum III - Data structure design 🔒 |
Easy (38.00%) |
design, hash-table, target-sum |
cpp |
| 0171.Excel Sheet Column Number |
Easy (63.66%) |
math |
cpp |
| 0172.Factorial Trailing Zeroes |
Medium (43.28%) |
math |
cpp |
| 0173.Binary Search Tree Iterator |
Medium (71.88%) |
design, stack, binary-tree |
cpp |
| 0174.Dungeon Game |
Hard (38.07%) |
dynamic-programming, matrix |
cpp |
| 0179.Largest Number |
Medium (36.04%) |
sort, string |
cpp |
| 0186.Reverse Words in a String II 🔒 |
Medium (54.52%) |
string, two-pointers |
cpp |
| 0187.Repeated DNA Sequences |
Medium (48.78%) |
hash-table, bit-manipulation, string |
cpp |
| 0188.Best Time to Buy and Sell Stock IV |
Hard (42.57%) |
dynamic-programming, best-time-to-buy-and-sell-stock |
cpp |
| 0189.Rotate Array |
Medium (40.50%) |
array |
cpp |
| 0190.Reverse Bits |
Easy (58.30%) |
bit-manipulation |
cpp |
| 0191.Number of 1 Bits |
Easy (70.75%) |
bit-manipulation |
cpp |
| 0198.House Robber |
Medium (50.95%) |
dynamic-programming, array |
cpp |
| 0199.Binary Tree Right Side View |
Medium (62.99%) |
binary-tree |
cpp |
| 0200.Number of Islands |
Medium (58.75%) |
depth-first-search, breadth-first-search |
cpp |
| 0201.Bitwise AND of Numbers Range |
Medium (46.86%) |
bit-manipulation |
cpp |
| 0202.Happy Number |
Easy (56.02%) |
hash-table, math, fast-slow-pointers |
cpp |
| 0203.Remove Linked List Elements |
Easy (48.63%) |
linked-list |
cpp |
| 0204.Count Primes |
Medium (33.56%) |
math |
cpp |
| 0205.Isomorphic Strings |
Easy (45.08%) |
hash-table |
cpp |
| 0206.Reverse Linked List |
Easy (76.41%) |
linked-list |
cpp |
| 0207.Course Schedule |
Medium (46.68%) |
graph, topological-sort, depth-first-search, breadth-first-search |
cpp |
| 0208.Implement Trie (Prefix Tree) |
Medium (64.99%) |
design, trie-tree |
cpp |
| 0209.Minimum Size Subarray Sum |
Medium (47.01%) |
array, sliding-window, binary-search, prefix-sum |
cpp |
| 0210.Course Schedule II |
Medium (50.32%) |
graph, topological-sort |
cpp |
| 0211.Design Add and Search Words Data Structure |
Medium (45.13%) |
trie, backtracking, design, depth-first-search |
cpp |
| 0212.Word Search II |
Hard (36.26%) |
trie, depth-first-search, backtracking, matrix |
cpp |
| 0213.House Robber II |
Medium (41.92%) |
dynamic-programming |
cpp |
| 0214.Shortest Palindrome |
Hard (33.37%) |
string, palindrome |
cpp |
| 0215.Kth Largest Element in an Array |
Medium (66.78%) |
heap, sort, divide-and-conquer, partition, array |
cpp |
| 0216.Combination Sum III |
Medium (69.54%) |
backtracking, combination |
cpp |
| 0217.Contains Duplicate |
Easy (61.59%) |
array, sort, hash-table, duplicate |
cpp |
| 0218.The Skyline Problem |
Hard (42.64%) |
sort, multiset |
cpp |
| 0219.Contains Duplicate II |
Easy (44.96%) |
array, hash-table, duplicate |
cpp |
| 0220.Contains Duplicate III |
Hard (22.72%) |
sliding-window, ordered-map, binary-search |
cpp |
| 0221.Maximal Square |
Medium (46.44%) |
dynamic-programming, matrix, prefix-sum |
cpp |
| 0222.Count Complete Tree Nodes |
Easy (64.95%) |
binary-tree, recursion |
cpp |
| 0223.Rectangle Area |
Medium (46.13%) |
math, geometry |
cpp |
| 0224.Basic Calculator |
Hard (43.36%) |
math, design, arithmetic, basic-calculator |
cpp |
| 0225.Implement Stack using Queues |
Easy (63.52%) |
stack, queue, design |
cpp |
| 0226.Invert Binary Tree |
Easy (76.86%) |
binary-tree, recursion |
cpp |
| 0227.Basic Calculator II |
Medium (43.53%) |
string, basic-calculator, stack, math, arithmetic |
cpp |
| 0228.Summary Ranges |
Easy (50.52%) |
array |
cpp |
| 0229.Majority Element II |
Medium (51.36%) |
array, boyer-moore-voting-algorithm |
cpp |
| 0230.Kth Smallest Element in a BST |
Medium (72.39%) |
binary-tree, binary-search-tree, divide-and-conquer |
cpp |
| 0231.Power of Two |
Easy (47.74%) |
bit-manipulation |
cpp |
| 0232.Implement Queue using Stacks |
Easy (66.16%) |
stack, queue, design |
cpp |
| 0233.Number of Digit One |
Hard (34.56%) |
math, digit |
cpp |
| 0234.Palindrome Linked List |
Easy (53.06%) |
linked-list, fast-slow-pointers, stack, recursion |
cpp |
| 0235.Lowest Common Ancestor of a Binary Search Tree |
Medium (64.58%) |
binary-search-tree |
cpp |
| 0236.Lowest Common Ancestor of a Binary Tree |
Medium (62.02%) |
binary-tree |
cpp |
| 0237.Delete Node in a Linked List |
Medium (78.35%) |
linked-list |
cpp |
| 0238.Product of Array Except Self |
Medium (66.09%) |
array |
cpp |
| 0239.Sliding Window Maximum |
Hard (46.55%) |
heap, sliding-window, monotonic-stack, deque, multiset |
cpp |
| 0240.Search a 2D Matrix II |
Medium (52.54%) |
binary-search, matrix |
cpp |
| 0241.Different Ways to Add Parentheses |
Medium (65.35%) |
divide-and-conquer, memoization |
cpp |
| 0242.Valid Anagram |
Easy (64.43%) |
hash-table |
cpp |
| 0243.Shortest Word Distance 🔒 |
Easy (65.30%) |
string, two-pointers |
cpp |
| 0244.Shortest Word Distance II 🔒 |
Medium (61.16%) |
design, hash-table, two-pointers |
cpp |
| 0245.Shortest Word Distance III 🔒 |
Medium (58.42%) |
string, two-pointers |
cpp |
| 0246.Strobogrammatic Number 🔒 |
Easy (47.68%) |
two-pointers |
cpp |
| 0247.Strobogrammatic Number II 🔒 |
Medium (52.23%) |
recursion, string |
cpp |
| 0248.Strobogrammatic Number III 🔒 |
Hard (42.11%) |
string, recursion |
cpp |
| 0249.Group Shifted Strings 🔒 |
Medium (65.51%) |
hash-table, string |
cpp |
| 0250.Count Univalue Subtrees 🔒 |
Medium (56.38%) |
binary-tree, depth-first-search |
cpp |
| 0251.Flatten 2D Vector 🔒 |
Medium (49.45%) |
design, two-pointers |
cpp |
| 0252.Meeting Rooms 🔒 |
Easy (58.02%) |
sort, interval |
cpp |
| 0253.Meeting Rooms II 🔒 |
Medium (51.22%) |
array, difference-array, interval |
cpp |
| 0254.Factor Combinations 🔒 |
Medium (49.47%) |
backtracking, math |
cpp |
| 0255.Verify Preorder Sequence in Binary Search Tree 🔒 |
Medium (49.51%) |
monotonic-stack, binary-search-tree, binary-tree |
cpp |
| 0256.Paint House 🔒 |
Medium (62.41%) |
dynamic-programming |
cpp |
| 0257.Binary Tree Paths |
Easy (63.51%) |
binary-tree, depth-first-search |
cpp |
| 0258.Add Digits |
Easy (66.53%) |
math |
cpp |
| 0259.3Sum Smaller 🔒 |
Medium (50.71%) |
array, two-pointers, sort |
cpp |
| 0260.Single Number III |
Medium (68.35%) |
bit-manipulation |
cpp |
| 0261.Graph Valid Tree 🔒 |
Medium (48.03%) |
tree, graph, union-find |
cpp |
| 0263.Ugly Number |
Easy (41.95%) |
easy |
cpp |
| 0264.Ugly Number II |
Medium (46.18%) |
heap, math, dynamic-programming |
cpp |
| 0265.Paint House II 🔒 |
Hard (54.60%) |
dynamic-programming |
cpp |
| 0266.Palindrome Permutation 🔒 |
Easy (67.15%) |
string, hash-table, palindrome, permutation |
cpp |
| 0267.Palindrome Permutation II 🔒 |
Medium (41.32%) |
string, permutation, palindrome, backtracking, hash-table |
cpp |
| 0268.Missing Number |
Easy (66.68%) |
math, array, bit-manipulation, binary-search |
cpp |
| 0269.Alien Dictionary 🔒 |
Hard (35.72%) |
graph, topological-sort, string |
cpp |
| 0270.Closest Binary Search Tree Value 🔒 |
Easy (51.80%) |
binary-search-tree, binary-tree, recursion |
cpp |
| 0271.Encode and Decode Strings 🔒 |
Medium (46.31%) |
string, design |
cpp |
| 0272.Closest Binary Search Tree Value II 🔒 |
Hard (59.01%) |
stack, queue, binary-search-tree, binary-tree |
cpp |
| 0273.Integer to English Words |
Hard (30.56%) |
math, string, hash-table |
cpp |
| 0274.H-Index |
Medium (38.89%) |
sort, array, hash-table |
cpp |
| 0275.H-Index II |
Medium (38.09%) |
binary-search |
cpp |
| 0276.Paint Fence 🔒 |
Medium (46.53%) |
dynamic-programming |
cpp |
| 0277.Find the Celebrity 🔒 |
Medium (47.14%) |
array, graph |
cpp |
| 0278.First Bad Version |
Easy (44.33%) |
binary-search |
cpp |
| 0279.Perfect Squares |
Medium (54.75%) |
math, dynamic-programming |
cpp |
| 0280.Wiggle Sort 🔒 |
Medium (67.64%) |
sort, array |
cpp |
| 0281.Zigzag Iterator 🔒 |
Medium (63.78%) |
design |
cpp |
| 0282.Expression Add Operators |
Hard (39.82%) |
recursion, string |
cpp |
| 0283.Move Zeroes |
Easy (61.71%) |
array, two-pointers, in-place-algorithm |
cpp |
| 0284.Peeking Iterator |
Medium (59.44%) |
design |
cpp |
| 0285.Inorder Successor in BST 🔒 |
Medium (49.63%) |
binary-search-tree, binary-tree, stack, recursion |
cpp |
| 0286.Walls and Gates 🔒 |
Medium (61.31%) |
breadth-first-search |
cpp |
| 0287.Find the Duplicate Number |
Medium (60.69%) |
array, duplicate, binary-search, bit-manipulation, fast-slow-pointers |
cpp |
| 0288.Unique Word Abbreviation 🔒 |
Medium (26.22%) |
hash-table, string |
cpp |
| 0289.Game of Life |
Medium (69.02%) |
matrix, bit-manipulation, in-place-algorithm |
cpp |
| 0290.Word Pattern |
Easy (42.00%) |
hash-table, string |
cpp |
| 0291.Word Pattern II 🔒 |
Medium (47.58%) |
backtracking, string, hash-table |
cpp |
| 0292.Nim Game |
Easy (56.81%) |
math, game-theory |
cpp |
| 0293.Flip Game 🔒 |
Easy (64.56%) |
string |
cpp |
| 0294.Flip Game II 🔒 |
Medium (52.12%) |
game, backtracking |
cpp |
| 0295.Find Median from Data Stream |
Hard (51.86%) |
design, heap |
cpp |
| 0296.Best Meeting Point 🔒 |
Hard (60.90%) |
math, sort |
cpp |
| 0297.Serialize and Deserialize Binary Tree |
Hard (56.66%) |
binary-tree, design, serialization |
cpp |
| 0298.Binary Tree Longest Consecutive Sequence 🔒 |
Medium (53.46%) |
binary-tree, depth-first-search |
cpp |
| 0299.Bulls and Cows |
Medium (50.24%) |
hash-table |
cpp |
| 0300.Longest Increasing Subsequence |
Medium (55.23%) |
array, dynamic-programming, greedy, binary-search |
cpp |
| 0301.Remove Invalid Parentheses |
Hard (48.14%) |
breadth-first-search, hash-table, parentheses, TODO |
cpp |
| 0302.Smallest Rectangle Enclosing Black Pixels 🔒 |
Hard (58.87%) |
binary-search, matrix, geometry |
cpp |
| 0303.Range Sum Query - Immutable |
Easy (63.17%) |
prefix-sum, math, array, interval |
cpp |
| 0304.Range Sum Query 2D - Immutable |
Medium (54.46%) |
prefix-sum, math, matrix, interval |
cpp |
| 0305.Number of Islands II 🔒 |
Hard (39.59%) |
union-find |
cpp |
| 0306.Additive Number |
Medium (31.53%) |
backtracking, string |
cpp |
| 0307.Range Sum Query - Mutable |
Medium (40.93%) |
array, interval, binary-indexed-tree |
cpp |
| 0308.Range Sum Query 2D - Mutable 🔒 |
Hard (44.01%) |
matrix, interval, binary-indexed-tree |
|
| 0309.Best Time to Buy and Sell Stock with Cooldown |
Medium (58.03%) |
dynamic-programming, best-time-to-buy-and-sell-stock |
cpp |
| 0310.Minimum Height Trees |
Medium (38.88%) |
tree, graph, topological-sort |
cpp |
| 0311.Sparse Matrix Multiplication 🔒 |
Medium (68.06%) |
math, matrix |
cpp |
| 0312.Burst Balloons |
Hard (58.68%) |
dynamic-programming |
cpp |
| 0313.Super Ugly Number |
Medium (45.25%) |
heap, math, dynamic-programming |
cpp |
| 0314.Binary Tree Vertical Order Traversal 🔒 |
Medium (54.18%) |
binary-tree, breadth-first-search, depth-first-search |
cpp |
| 0315.Count of Smaller Numbers After Self |
Hard (42.41%) |
sort, binary-indexed-tree, interval, merge-sort, hash-table, segment-tree |
cpp |
| 0316.Remove Duplicate Letters |
Medium (49.58%) |
stack, greedy, hash-table, string |
cpp |
| 0317.Shortest Distance from All Buildings 🔒 |
Hard (43.13%) |
breadth-first-search |
cpp |
| 0318.Maximum Product of Word Lengths |
Medium (59.93%) |
bit-manipulation |
cpp |
| 0319.Bulb Switcher |
Medium (52.72%) |
math, brainteaser |
cpp |
| 0320.Generalized Abbreviation 🔒 |
Medium (58.36%) |
string, depth-first-search |
cpp |
| 0321.Create Maximum Number |
Hard (30.01%) |
greedy |
cpp |
| 0322.Coin Change |
Medium (43.81%) |
dynamic-programming, memoization, depth-first-search, coin-change |
cpp |
| 0323.Number of Connected Components in an Undirected Graph 🔒 |
Medium (62.76%) |
graph, depth-first-search, union-find |
cpp |
| 0324.Wiggle Sort II |
Medium (34.28%) |
sort, array, two-pointers, partition |
cpp |
| 0325.Maximum Size Subarray Sum Equals k 🔒 |
Medium (49.48%) |
hash-table, prefix-sum |
cpp |
| 0326.Power of Three |
Easy (46.50%) |
math |
cpp |
| 0327.Count of Range Sum |
Hard (35.90%) |
array, interval, merge-sort, binary-indexed-tree, segment-tree, hash-table |
cpp |
| 0328.Odd Even Linked List |
Medium (61.39%) |
linked-list |
cpp |
| 0329.Longest Increasing Path in a Matrix |
Hard (53.53%) |
depth-first-search, breadth-first-search, memoization |
cpp |
| 0330.Patching Array |
Hard (41.72%) |
greedy |
cpp |
| 0331.Verify Preorder Serialization of a Binary Tree |
Medium (45.18%) |
stack |
cpp |
| 0332.Reconstruct Itinerary |
Hard (43.24%) |
graph, depth-first-search, sort, stack |
cpp |
| 0333.Largest BST Subtree 🔒 |
Medium (43.73%) |
binary-tree, depth-first-search |
cpp |
| 0334.Increasing Triplet Subsequence |
Medium (40.00%) |
array |
cpp |
| 0335.Self Crossing |
Hard (30.43%) |
math, geometry |
cpp |
| 0336.Palindrome Pairs |
Hard (35.27%) |
hash-table, string, ordered-set |
cpp |
| 0337.House Robber III |
Medium (54.23%) |
binary-tree, depth-first-search |
cpp |
| 0338.Counting Bits |
Easy (78.20%) |
bit-manipulation, dynamic-programming |
cpp |
| 0339.Nested List Weight Sum 🔒 |
Medium (83.47%) |
depth-first-search, breadth-first-search |
cpp |
| 0340.Longest Substring with At Most K Distinct Characters 🔒 |
Medium (48.78%) |
string, hash-table, sliding-window |
cpp |
| 0341.Flatten Nested List Iterator |
Medium (64.43%) |
design, stack, queue, depth-first-search |
cpp |
| 0342.Power of Four |
Easy (47.94%) |
bit-manipulation, math |
cpp |
| 0343.Integer Break |
Medium (60.29%) |
math |
cpp |
| 0344.Reverse String |
Easy (77.76%) |
two-pointers, string |
cpp |
| 0345.Reverse Vowels of a String |
Easy (52.91%) |
two-pointers, string |
cpp |
| 0346.Moving Average from Data Stream 🔒 |
Easy (78.24%) |
queue, design |
cpp |
| 0347.Top K Frequent Elements |
Medium (62.74%) |
hash-table, heap |
cpp |
| 0348.Design Tic-Tac-Toe 🔒 |
Medium (57.93%) |
design, hash-table |
cpp |
| 0349.Intersection of Two Arrays |
Easy (74.39%) |
hash-table, two-pointers, binary-search, sort, set |
cpp |
| 0350.Intersection of Two Arrays II |
Easy (56.45%) |
hash-table, sort, two-pointers |
cpp |
| 0351.Android Unlock Patterns 🔒 |
Medium (51.81%) |
depth-first-search |
cpp |
| 0352.Data Stream as Disjoint Intervals |
Hard (59.98%) |
interval, ordered-map |
cpp |
| 0353.Design Snake Game 🔒 |
Medium (38.73%) |
design, queue, hash-table |
cpp |
| 0354.Russian Doll Envelopes |
Hard (37.11%) |
binary-search, sort, greedy |
cpp |
| 0355.Design Twitter |
Medium (39.32%) |
design, hash-table, heap |
cpp |
| 0356.Line Reflection 🔒 |
Medium (35.44%) |
hash-table, geometry |
cpp |
| 0357.Count Numbers with Unique Digits |
Medium (52.86%) |
math, backtracking |
cpp |
| 0358.Rearrange String k Distance Apart 🔒 |
Hard (38.62%) |
heap, greedy, hash-table |
cpp |
| 0359.Logger Rate Limiter 🔒 |
Easy (75.84%) |
design, hash-table |
cpp |
| 0360.Sort Transformed Array 🔒 |
Medium (55.69%) |
math, two-pointers |
cpp |
| 0361.Bomb Enemy 🔒 |
Medium (51.72%) |
matrix |
cpp |
| 0362.Design Hit Counter 🔒 |
Medium (68.64%) |
design, binary-search |
cpp |
| 0363.Max Sum of Rectangle No Larger Than K |
Hard (44.11%) |
binary-search, matrix, prefix-sum, ordered-set |
cpp |
| 0364.Nested List Weight Sum II 🔒 |
Medium (65.28%) |
depth-first-search |
cpp |
| 0365.Water and Jug Problem |
Medium (40.21%) |
math |
cpp |
| 0366.Find Leaves of Binary Tree 🔒 |
Medium (80.54%) |
binary-tree, depth-first-search |
cpp |
| 0367.Valid Perfect Square |
Easy (43.61%) |
math, binary-search |
cpp |
| 0368.Largest Divisible Subset |
Medium (45.24%) |
math, dynamic-programming |
cpp |
| 0369.Plus One Linked List 🔒 |
Medium (61.02%) |
linked-list, recursion |
cpp |
| 0370.Range Addition 🔒 |
Medium (71.55%) |
difference-array |
cpp |
| 0371.Sum of Two Integers |
Medium (51.78%) |
bit-manipulation, arithmetic |
cpp |
| 0372.Super Pow |
Medium (35.20%) |
math |
cpp |
| 0373.Find K Pairs with Smallest Sums |
Medium (39.98%) |
heap, sort, array |
cpp |
| 0374.Guess Number Higher or Lower |
Easy (53.39%) |
binary-search |
cpp |
| 0375.Guess Number Higher or Lower II |
Medium (48.83%) |
dynamic-programming |
cpp |
| 0376.Wiggle Subsequence |
Medium (48.45%) |
dynamic-programming, greedy |
cpp |
| 0377.Combination Sum IV |
Medium (54.13%) |
dynamic-programming, array, combination |
cpp |
| 0378.Kth Smallest Element in a Sorted Matrix |
Medium (62.38%) |
binary-search, matrix |
cpp |
| 0379.Design Phone Directory 🔒 |
Medium (51.65%) |
design, hash-table |
cpp |
| 0380.Insert Delete GetRandom O(1) |
Medium (54.41%) |
array, hash-table, design, random |
cpp |
| 0381.Insert Delete GetRandom O(1) - Duplicates allowed |
Hard (35.44%) |
array, hash-table, design, random |
cpp |
| 0382.Linked List Random Node |
Medium (63.13%) |
random, reservoir-sampling |
cpp |
| 0383.Ransom Note |
Easy (61.20%) |
hash-table, string, easy |
cpp |
| 0384.Shuffle an Array |
Medium (58.28%) |
random |
cpp |
| 0385.Mini Parser |
Medium (38.03%) |
string, stack, recursion |
cpp |
| 0386.Lexicographical Numbers |
Medium (63.77%) |
math, string, depth-first-search |
cpp |
| 0387.First Unique Character in a String |
Easy (62.09%) |
hash-table |
cpp |
| 0388.Longest Absolute File Path |
Medium (47.24%) |
stack, hash-table |
cpp |
| 0389.Find the Difference |
Easy (59.77%) |
hash-table |
cpp |
| 0390.Elimination Game |
Medium (45.70%) |
math |
cpp |
| 0391.Perfect Rectangle |
Hard (33.63%) |
hash-table, geometry, hard |
cpp |
| 0392.Is Subsequence |
Easy (47.93%) |
string, two-pointers |
cpp |
| 0393.UTF-8 Validation |
Medium (45.11%) |
bit-manipulation |
cpp |
| 0394.Decode String |
Medium (59.08%) |
stack, string |
cpp |
| 0395.Longest Substring with At Least K Repeating Characters |
Medium (44.96%) |
string, sliding-window, hash-table |
cpp |
| 0396.Rotate Function |
Medium (42.45%) |
math |
cpp |
| 0397.Integer Replacement |
Medium (35.70%) |
bit-manipulation, math, recursion |
cpp |
| 0398.Random Pick Index |
Medium (63.18%) |
random, hash-table, reservoir-sampling |
cpp |
| 0399.Evaluate Division |
Medium (61.62%) |
union-find, graph, depth-first-search |
cpp |
| 0400.Nth Digit |
Medium (34.75%) |
math |
cpp |
| 0401.Binary Watch |
Easy (54.15%) |
bit-manipulation |
cpp |
| 0402.Remove K Digits |
Medium (31.73%) |
stack, greedy |
cpp |
| 0403.Frog Jump |
Hard (46.01%) |
binary-search, hash-table, depth-first-search, memoization |
cpp |
| 0404.Sum of Left Leaves |
Easy (57.80%) |
binary-tree |
cpp |
| 0405.Convert a Number to Hexadecimal |
Easy (48.31%) |
bit-manipulation |
cpp |
| 0406.Queue Reconstruction by Height |
Medium (73.40%) |
sort |
cpp |
| 0407.Trapping Rain Water II |
Hard (47.89%) |
heap, breadth-first-search |
cpp |
| 0408.Valid Word Abbreviation 🔒 |
Easy (35.65%) |
string, two-pointers |
cpp |
| 0409.Longest Palindrome |
Easy (53.90%) |
hash-table, string, palindrome |
cpp |
| 0410.Split Array Largest Sum |
Hard (55.20%) |
binary-search, dynamic-programming, prefix-sum, array, target-sum |
cpp |
| 0411.Minimum Unique Word Abbreviation 🔒 |
Hard (39.71%) |
heap, bit-manipulation, string |
cpp |
| 0412.Fizz Buzz |
Easy (72.00%) |
easy |
cpp |
| 0413.Arithmetic Slices |
Medium (65.04%) |
math, dynamic-programming |
cpp |
| 0414.Third Maximum Number |
Easy (34.76%) |
array |
cpp |
| 0415.Add Strings |
Easy (51.71%) |
string, arithmetic, two-pointers |
cpp |
| 0416.Partition Equal Subset Sum |
Medium (46.25%) |
dynamic-programming, bit-manipulation, array, target-sum |
cpp |
| 0417.Pacific Atlantic Water Flow |
Medium (55.15%) |
depth-first-search, breadth-first-search, matrix |
cpp |
| 0418.Sentence Screen Fitting 🔒 |
Medium (36.10%) |
greedy |
cpp |
| 0419.Battleships in a Board |
Medium (75.30%) |
matrix |
cpp |
| 0420.Strong Password Checker |
Hard (13.60%) |
string, hard, heap |
cpp |
| 0421.Maximum XOR of Two Numbers in an Array |
Medium (53.32%) |
bit-manipulation, trie, array |
cpp |
| 0422.Valid Word Square 🔒 |
Easy (40.91%) |
matrix, string |
cpp |
| 0423.Reconstruct Original Digits from English |
Medium (51.10%) |
string, math |
cpp |
| 0424.Longest Repeating Character Replacement |
Medium (53.72%) |
string, sliding-window |
cpp |
| 0425.Word Squares 🔒 |
Hard (53.30%) |
trie, backtracking, string |
cpp |
| 0426.Convert Binary Search Tree to Sorted Doubly Linked List 🔒 |
Medium (64.77%) |
binary-tree, binary-search-tree, linked-list, recursion |
cpp |
| 0427.Construct Quad Tree |
Medium (75.29%) |
matrix, depth-first-search |
cpp |
| 0428.Serialize and Deserialize N-ary Tree 🔒 |
Hard (66.89%) |
tree, depth-first-search, breadth-first-search, design, serialization |
cpp |
| 0429.N-ary Tree Level Order Traversal |
Medium (70.82%) |
tree, breadth-first-search, depth-first-search |
cpp |
| 0430.Flatten a Multilevel Doubly Linked List |
Medium (60.03%) |
linked-list, stack, recursion |
cpp |
| 0431.Encode N-ary Tree to Binary Tree 🔒 |
Hard (79.41%) |
binary-tree, tree, recursion |
cpp |
| 0432.All O`one Data Structure |
Hard (36.73%) |
hash-table, design, linked-list |
cpp |
| 0433.Minimum Genetic Mutation |
Medium (53.59%) |
breadth-first-search |
cpp |
| 0434.Number of Segments in a String |
Easy (36.40%) |
string |
cpp |
| 0435.Non-overlapping Intervals |
Medium (53.13%) |
sort, greedy, interval |
cpp |
| 0436.Find Right Interval |
Medium (51.99%) |
sort, array, binary-search, interval |
cpp |
| 0437.Path Sum III |
Medium (46.43%) |
binary-tree, hash-table, depth-first-search, prefix-sum |
cpp |
| 0438.Find All Anagrams in a String |
Medium (50.86%) |
sliding-window, hash-table |
cpp |
| 0439.Ternary Expression Parser 🔒 |
Medium (60.77%) |
stack, string |
cpp |
| 0440.K-th Smallest in Lexicographical Order |
Hard (32.14%) |
tree, depth-first-search |
cpp |
| 0441.Arranging Coins |
Easy (46.55%) |
math, binary-search |
cpp |
| 0442.Find All Duplicates in an Array |
Medium (75.66%) |
array, duplicate |
cpp |
| 0443.String Compression |
Medium (54.27%) |
two-pointers |
cpp |
| 0444.Sequence Reconstruction 🔒 |
Medium (28.08%) |
graph, topological-sort |
cpp |
| 0445.Add Two Numbers II |
Medium (61.12%) |
linked-list, arithmetic |
cpp |
| 0446.Arithmetic Slices II - Subsequence |
Hard (54.58%) |
dynamic-programming, hash-table |
cpp |
| 0447.Number of Boomerangs |
Medium (55.40%) |
hash-table, math |
cpp |
| 0448.Find All Numbers Disappeared in an Array |
Easy (60.91%) |
array, hash-table |
cpp |
| 0449.Serialize and Deserialize BST |
Medium (57.62%) |
binary-search-tree, binary-tree, design, monotonous-stack, serialization |
cpp |
| 0450.Delete Node in a BST |
Medium (51.17%) |
binary-search-tree, binary-tree, recursion |
cpp |
| 0451.Sort Characters By Frequency |
Medium (72.51%) |
hash-table, heap, sort, string, bucket-sort |
cpp |
| 0452.Minimum Number of Arrows to Burst Balloons |
Medium (58.87%) |
interval, greedy, sort |
cpp |
| 0453.Minimum Moves to Equal Array Elements |
Medium (56.69%) |
array, math |
cpp |
| 0454.4Sum II |
Medium (57.23%) |
hash-table |
cpp |
| 0455.Assign Cookies |
Easy (52.67%) |
greedy |
cpp |
| 0456.132 Pattern |
Medium (33.75%) |
monotonic-stack, array |
cpp |
| 0457.Circular Array Loop |
Medium (33.92%) |
fast-slow-pointers, array |
cpp |
| 0458.Poor Pigs |
Hard (59.75%) |
math |
cpp |
| 0459.Repeated Substring Pattern |
Easy (46.07%) |
string |
cpp |
| 0460.LFU Cache |
Hard (44.11%) |
design |
cpp |
| 0461.Hamming Distance |
Easy (75.37%) |
bit-manipulation |
cpp |
| 0462.Minimum Moves to Equal Array Elements II |
Medium (60.10%) |
sort, partition |
cpp |
| 0463.Island Perimeter |
Easy (70.35%) |
geometry |
cpp |
| 0464.Can I Win |
Medium (29.66%) |
depth-first-search, memoization, minimax |
cpp |
| 0465.Optimal Account Balancing 🔒 |
Hard (49.56%) |
bit-manipulation, dynamic-programming |
cpp |
| 0466.Count The Repetitions |
Hard (30.12%) |
string, hard |
cpp |
| 0467.Unique Substrings in Wraparound String |
Medium (39.56%) |
dynamic-programming |
cpp |
| 0468.Validate IP Address |
Medium (26.95%) |
string |
cpp |
| 0469.Convex Polygon 🔒 |
Medium (39.38%) |
math, geometry |
cpp |
| 0470.Implement Rand10() Using Rand7() |
Medium (45.97%) |
math, random |
cpp |
| 0471.Encode String with Shortest Length 🔒 |
Hard (50.43%) |
string, dynamic-programming |
cpp |
| 0472.Concatenated Words |
Hard (49.46%) |
string, trie, depth-first-search |
cpp |
| 0473.Matchsticks to Square |
Medium (40.24%) |
depth-first-search, dynamic-programming, bit-manipulation, backtracking |
cpp |
| 0474.Ones and Zeroes |
Medium (47.53%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 0475.Heaters |
Medium (37.73%) |
binary-search, sort |
cpp |
| 0476.Number Complement |
Easy (67.60%) |
bit-manipulation |
cpp |
| 0477.Total Hamming Distance |
Medium (52.55%) |
bit-manipulation |
cpp |
| 0478.Generate Random Point in a Circle |
Medium (39.78%) |
geometry, random, math |
cpp |
| 0479.Largest Palindrome Product |
Hard (33.18%) |
math, palindrome |
cpp |
| 0480.Sliding Window Median |
Hard (39.25%) |
sliding-window, multiset, heap, hash-table, hard |
cpp |
| 0481.Magical String |
Medium (51.20%) |
math, string |
cpp |
| 0482.License Key Formatting |
Easy (43.72%) |
string |
cpp |
| 0483.Smallest Good Base |
Hard (40.44%) |
math, binary-search, hard |
cpp |
| 0484.Find Permutation 🔒 |
Medium (66.86%) |
string, permutation, greedy |
cpp |
| 0485.Max Consecutive Ones |
Easy (58.89%) |
array |
cpp |
| 0486.Predict the Winner |
Medium (55.45%) |
minimax, dynamic-programming, game-theory, depth-first-search, memoization |
cpp |
| 0487.Max Consecutive Ones II 🔒 |
Medium (50.33%) |
array, sliding-window |
cpp |
| 0488.Zuma Game |
Hard (32.92%) |
recursion, depth-first-search, memoization |
cpp |
| 0489.Robot Room Cleaner 🔒 |
Hard (76.67%) |
depth-first-search |
cpp |
| 0490.The Maze 🔒 |
Medium (57.78%) |
breadth-first-search |
cpp |
| 0491.Non-decreasing Subsequences |
Medium (60.65%) |
depth-first-search, array |
cpp |
| 0492.Construct the Rectangle |
Easy (57.37%) |
math, geometry |
cpp |
| 0493.Reverse Pairs |
Hard (30.57%) |
array, merge-sort, binary-indexed-tree, segment-tree, hash-table |
cpp |
| 0494.Target Sum |
Medium (46.70%) |
dynamic-programming, array, arithmetic |
cpp |
| 0495.Teemo Attacking |
Easy (56.56%) |
array |
cpp |
| 0496.Next Greater Element I |
Easy (72.13%) |
array, stack, monotonic-stack, hash-table |
cpp |
| 0497.Random Point in Non-overlapping Rectangles |
Medium (39.95%) |
prefix-sum, random, binary-search |
cpp |
| 0498.Diagonal Traverse |
Medium (60.06%) |
matrix |
cpp |
| 0499.The Maze III 🔒 |
Hard (48.67%) |
breadth-first-search |
cpp |
| 0500.Keyboard Row |
Easy (70.61%) |
hash-table |
cpp |
| 0501.Find Mode in Binary Search Tree |
Easy (56.03%) |
binary-search-tree, binary-tree |
cpp |
| 0502.IPO |
Hard (49.55%) |
heap, sort, greedy |
cpp |
| 0503.Next Greater Element II |
Medium (63.78%) |
monotonic-stack, array |
cpp |
| 0504.Base 7 |
Easy (49.89%) |
math |
cpp |
| 0505.The Maze II 🔒 |
Medium (53.35%) |
breadth-first-search |
cpp |
| 0506.Relative Ranks |
Easy (63.70%) |
array, sort, heap, ordered-map, hash-table |
cpp |
| 0507.Perfect Number |
Easy (40.16%) |
math |
cpp |
| 0508.Most Frequent Subtree Sum |
Medium (66.27%) |
binary-tree, hash-table, depth-first-search |
cpp |
| 0509.Fibonacci Number |
Easy (70.93%) |
fibonacci, dynamic-programming |
cpp |
| 0510.Inorder Successor in BST II 🔒 |
Medium (60.92%) |
binary-tree, binary-search-tree |
cpp |
| 0513.Find Bottom Left Tree Value |
Medium (71.09%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0514.Freedom Trail |
Hard (47.72%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 0515.Find Largest Value in Each Tree Row |
Medium (65.66%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0516.Longest Palindromic Subsequence |
Medium (62.52%) |
dynamic-programming, palindrome |
cpp |
| 0517.Super Washing Machines |
Hard (41.14%) |
math, greedy |
cpp |
| 0518.Coin Change II |
Medium (63.76%) |
dynamic-programming, coin-change |
cpp |
| 0519.Random Flip Matrix |
Medium (41.82%) |
random, design, array |
cpp |
| 0520.Detect Capital |
Easy (56.50%) |
string |
cpp |
| 0521.Longest Uncommon Subsequence I |
Easy (60.69%) |
string |
cpp |
| 0522.Longest Uncommon Subsequence II |
Medium (41.28%) |
string, sort, two-pointers |
cpp |
| 0523.Continuous Subarray Sum |
Medium (28.87%) |
prefix-sum, hash-table |
cpp |
| 0524.Longest Word in Dictionary through Deleting |
Medium (51.16%) |
two-pointers, sort, string |
cpp |
| 0525.Contiguous Array |
Medium (48.93%) |
hash-table, array, prefix-sum |
cpp |
| 0526.Beautiful Arrangement |
Medium (64.24%) |
permutation, recursion |
cpp |
| 0527.Word Abbreviation 🔒 |
Hard (60.95%) |
trie, string |
cpp |
| 0528.Random Pick with Weight |
Medium (46.73%) |
prefix-sum, random, binary-search |
cpp |
| 0529.Minesweeper |
Medium (66.54%) |
matrix, depth-first-search, design |
cpp |
| 0530.Minimum Absolute Difference in BST |
Easy (58.39%) |
binary-search-tree, binary-tree |
cpp |
| 0531.Lonely Pixel I 🔒 |
Medium (62.26%) |
matrix |
cpp |
| 0532.K-diff Pairs in an Array |
Medium (42.70%) |
array, hash-table |
cpp |
| 0533.Lonely Pixel II 🔒 |
Medium (48.59%) |
matrix, array |
cpp |
| 0535.Encode and Decode TinyURL |
Medium (86.33%) |
hash-table, design |
cpp |
| 0536.Construct Binary Tree from String 🔒 |
Medium (56.81%) |
binary-tree, string, recursion |
cpp |
| 0537.Complex Number Multiplication |
Medium (71.75%) |
math, string, arithmetic |
cpp |
| 0538.Convert BST to Greater Tree |
Medium (68.94%) |
binary-search-tree, binary-tree, stack |
cpp |
| 0539.Minimum Time Difference |
Medium (56.81%) |
string, array, sort, bitmap |
cpp |
| 0540.Single Element in a Sorted Array |
Medium (59.01%) |
binary-search, bit-manipulation, duplicate |
cpp |
| 0541.Reverse String II |
Easy (50.63%) |
string |
cpp |
| 0542.01 Matrix |
Medium (48.33%) |
breadth-first-search, matrix, dynamic-programming |
cpp |
| 0543.Diameter of Binary Tree |
Easy (60.21%) |
binary-tree, depth-first-search |
cpp |
| 0544.Output Contest Matches 🔒 |
Medium (77.11%) |
array |
cpp |
| 0545.Boundary of Binary Tree 🔒 |
Medium (45.32%) |
binary-tree |
cpp |
| 0546.Remove Boxes |
Hard (47.74%) |
depth-first-search, memoization, hard |
cpp |
| 0547.Number of Provinces |
Medium (66.08%) |
graph, union-find |
cpp |
| 0548.Split Array with Equal Sum 🔒 |
Hard (50.11%) |
prefix-sum, hash-table |
cpp |
| 0549.Binary Tree Longest Consecutive Sequence II 🔒 |
Medium (49.47%) |
binary-tree, depth-first-search |
cpp |
| 0551.Student Attendance Record I |
Easy (48.72%) |
string, regex |
cpp |
| 0552.Student Attendance Record II |
Hard (42.71%) |
depth-first-search, memoization |
cpp |
| 0553.Optimal Division |
Medium (60.69%) |
math |
cpp |
| 0554.Brick Wall |
Medium (54.72%) |
hash-table |
cpp |
| 0555.Split Concatenated Strings 🔒 |
Medium (43.46%) |
greedy, string |
cpp |
| 0556.Next Greater Element III |
Medium (34.02%) |
permutation, string |
cpp |
| 0557.Reverse Words in a String III |
Easy (83.03%) |
string, stack, two-pointers |
cpp |
| 0558.Logical OR of Two Binary Grids Represented as Quad-Trees |
Medium (49.55%) |
tree, depth-first-search |
cpp |
| 0559.Maximum Depth of N-ary Tree |
Easy (72.11%) |
tree, depth-first-search |
cpp |
| 0560.Subarray Sum Equals K |
Medium (43.54%) |
array, hash-table, prefix-sum |
cpp |
| 0561.Array Partition |
Easy (78.71%) |
array, sort |
cpp |
| 0562.Longest Line of Consecutive One in Matrix 🔒 |
Medium (50.36%) |
dynamic-programming, matrix |
cpp |
| 0563.Binary Tree Tilt |
Easy (61.69%) |
binary-tree, depth-first-search |
cpp |
| 0564.Find the Closest Palindrome |
Hard (22.28%) |
palindrome, string |
cpp |
| 0565.Array Nesting |
Medium (56.34%) |
array |
cpp |
| 0566.Reshape the Matrix |
Easy (63.08%) |
matrix |
cpp |
| 0567.Permutation in String |
Medium (44.33%) |
sliding-window, hash-table, string |
cpp |
| 0568.Maximum Vacation Days 🔒 |
Hard (45.57%) |
dynamic-programming |
cpp |
| 0572.Subtree of Another Tree |
Easy (47.78%) |
binary-tree, depth-first-search |
cpp |
| 0573.Squirrel Simulation 🔒 |
Medium (57.10%) |
planning, greedy |
cpp |
| 0575.Distribute Candies |
Easy (67.58%) |
hash-table |
cpp |
| 0576.Out of Boundary Paths |
Medium (48.07%) |
dynamic-programming, depth-first-search, memoization, matrix |
cpp |
| 0581.Shortest Unsorted Continuous Subarray |
Medium (36.81%) |
array, sort, two-pointers, sliding-window |
cpp |
| 0582.Kill Process 🔒 |
Medium (69.27%) |
tree, graph, depth-first-search |
cpp |
| 0583.Delete Operation for Two Strings |
Medium (61.47%) |
string, dynamic-programming |
cpp |
| 0587.Erect the Fence |
Hard (51.92%) |
geometry |
cpp |
| 0588.Design In-Memory File System 🔒 |
Hard (48.14%) |
design, hash-table, trie |
cpp |
| 0589.N-ary Tree Preorder Traversal |
Easy (75.46%) |
stack, tree |
cpp |
| 0590.N-ary Tree Postorder Traversal |
Easy (77.84%) |
stack, tree |
cpp |
| 0591.Tag Validator |
Hard (38.14%) |
string, stack |
cpp |
| 0592.Fraction Addition and Subtraction |
Medium (53.15%) |
math, string, arithmetic, greatest-common-divisor |
cpp |
| 0593.Valid Square |
Medium (43.99%) |
math, hash-table, geometry |
cpp |
| 0594.Longest Harmonious Subsequence |
Easy (54.60%) |
hash-table, array, ordered-map, sliding-window, sort |
cpp |
| 0598.Range Addition II |
Easy (56.04%) |
math, matrix |
cpp |
| 0599.Minimum Index Sum of Two Lists |
Easy (55.26%) |
hash-table, string |
cpp |
| 0600.Non-negative Integers without Consecutive Ones |
Hard (39.71%) |
math, dynamic-programming, bit-manipulation |
cpp |
| 0604.Design Compressed String Iterator 🔒 |
Easy (39.74%) |
design, string |
cpp |
| 0605.Can Place Flowers |
Easy (29.25%) |
array, greedy |
cpp |
| 0606.Construct String from Binary Tree |
Medium (69.13%) |
binary-tree, string |
cpp |
| 0609.Find Duplicate File in System |
Medium (67.62%) |
hash-table, string |
cpp |
| 0611.Valid Triangle Number |
Medium (51.09%) |
binary-search, array, sort, two-pointers |
cpp |
| 0616.Add Bold Tag in String 🔒 |
Medium (49.67%) |
string, trie |
cpp |
| 0617.Merge Two Binary Trees |
Easy (78.91%) |
binary-tree, depth-first-search |
cpp |
| 0621.Task Scheduler |
Medium (59.85%) |
array, hash-table, greedy |
cpp |
| 0622.Design Circular Queue |
Medium (51.41%) |
design, queue, linked-list, array |
cpp |
| 0623.Add One Row to Tree |
Medium (59.63%) |
binary-tree, depth-first-search, breadth-first-search |
cpp |
| 0624.Maximum Distance in Arrays |
Medium (42.41%) |
array |
cpp |
| 0625.Minimum Factorization 🔒 |
Medium (33.59%) |
greedy, math |
cpp |
| 0628.Maximum Product of Three Numbers |
Easy (45.30%) |
sort, math, array, greedy |
cpp |
| 0629.K Inverse Pairs Array |
Hard (50.04%) |
dynamic-programming, array, math |
cpp |
| 0630.Course Schedule III |
Hard (40.18%) |
greedy, heap |
cpp |
| 0631.Design Excel Sum Formula 🔒 |
Hard (43.69%) |
design, matrix |
cpp |
| 0632.Smallest Range Covering Elements from K Lists |
Hard (62.41%) |
heap, hash-table, sort, sliding-window |
cpp |
| 0633.Sum of Square Numbers |
Medium (33.97%) |
math, two-pointers |
cpp |
| 0634.Find the Derangement of An Array 🔒 |
Medium (41.95%) |
dynamic-programming |
cpp |
| 0635.Design Log Storage System 🔒 |
Medium (61.39%) |
string, design, ordered-map, binary-search |
cpp |
| 0636.Exclusive Time of Functions |
Medium (62.44%) |
stack |
cpp |
| 0637.Average of Levels in Binary Tree |
Easy (72.43%) |
binary-tree |
cpp |
| 0638.Shopping Offers |
Medium (52.17%) |
memorization, recursion |
cpp |
| 0639.Decode Ways II |
Hard (30.69%) |
dynamic-programming |
cpp |
| 0640.Solve the Equation |
Medium (43.73%) |
math, string |
cpp |
| 0641.Design Circular Deque |
Medium (56.86%) |
design, queue, linked-list, array |
cpp |
| 0642.Design Search Autocomplete System 🔒 |
Hard (48.89%) |
trie, string, design, sort |
cpp |
| 0643.Maximum Average Subarray I |
Easy (43.26%) |
array, sliding-window, prefix-sum |
cpp |
| 0644.Maximum Average Subarray II 🔒 |
Hard (36.64%) |
binary-search, array, prefix-sum |
cpp |
| 0645.Set Mismatch |
Easy (44.54%) |
hash-table, math, in-place |
cpp |
| 0646.Maximum Length of Pair Chain |
Medium (59.76%) |
dynamic-programming, greedy, sort |
cpp |
| 0647.Palindromic Substrings |
Medium (70.05%) |
string, dynamic-programming, palindrome, manacher |
cpp |
| 0648.Replace Words |
Medium (62.82%) |
hash-table, trie, sort |
cpp |
| 0649.Dota2 Senate |
Medium (47.53%) |
greedy, queue |
cpp |
| 0650.2 Keys Keyboard |
Medium (54.06%) |
dynamic-programming, math |
cpp |
| 0651.4 Keys Keyboard 🔒 |
Medium (56.09%) |
dynamic-programming |
cpp |
| 0652.Find Duplicate Subtrees |
Medium (59.38%) |
binary-tree, serialization |
cpp |
| 0653.Two Sum IV - Input is a BST |
Easy (61.20%) |
binary-search-tree, binary-tree, hash-table |
cpp |
| 0654.Maximum Binary Tree |
Medium (85.32%) |
binary-tree, array, monotonic-stack, divide-and-conquer |
cpp |
| 0655.Print Binary Tree |
Medium (63.42%) |
binary-tree |
cpp |
| 0656.Coin Path 🔒 |
Hard (32.05%) |
dynamic-programming |
cpp |
| 0657.Robot Return to Origin |
Easy (75.68%) |
easy |
cpp |
| 0658.Find K Closest Elements |
Medium (47.31%) |
binary-search, two-pointers |
cpp |
| 0659.Split Array into Consecutive Subsequences |
Medium (51.03%) |
hash-table, greedy |
cpp |
| 0660.Remove 9 🔒 |
Hard (57.42%) |
math |
cpp |
| 0661.Image Smoother |
Easy (67.23%) |
matrix |
cpp |
| 0662.Maximum Width of Binary Tree |
Medium (42.95%) |
binary-tree |
cpp |
| 0663.Equal Tree Partition 🔒 |
Medium (41.47%) |
binary-tree, depth-first-search, hash-table |
cpp |
| 0664.Strange Printer |
Hard (54.96%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 0665.Non-decreasing Array |
Medium (24.66%) |
array |
cpp |
| 0666.Path Sum IV 🔒 |
Medium (60.94%) |
binary-tree, hash-table |
cpp |
| 0667.Beautiful Arrangement II |
Medium (60.13%) |
array, greedy, math, brainteaser |
cpp |
| 0668.Kth Smallest Number in Multiplication Table |
Hard (51.62%) |
matrix, binary-search |
cpp |
| 0669.Trim a Binary Search Tree |
Medium (66.26%) |
binary-search-tree, binary-tree, depth-first-search |
cpp |
| 0670.Maximum Swap |
Medium (48.58%) |
math, greedy |
cpp |
| 0671.Second Minimum Node In a Binary Tree |
Easy (44.50%) |
binary-tree, depth-first-search |
cpp |
| 0672.Bulb Switcher II |
Medium (50.07%) |
math, bit-manipulation |
cpp |
| 0673.Number of Longest Increasing Subsequence |
Medium (47.90%) |
array, dynamic-programming |
cpp |
| 0674.Longest Continuous Increasing Subsequence |
Easy (50.17%) |
array |
cpp |
| 0675.Cut Off Trees for Golf Event |
Hard (34.30%) |
sort, breadth-first-search, heap |
cpp |
| 0676.Implement Magic Dictionary |
Medium (57.33%) |
hash-table, string, trie, design, depth-first-search |
cpp |
| 0677.Map Sum Pairs |
Medium (56.70%) |
trie, hash-table, design, string, ordered-map |
cpp |
| 0678.Valid Parenthesis String |
Medium (37.87%) |
string, dynamic-programming, greedy |
cpp |
| 0679.24 Game |
Hard (49.32%) |
depth-first-search, arithmetic |
cpp |
| 0680.Valid Palindrome II |
Easy (40.56%) |
string, palindrome, two-pointers |
cpp |
| 0681.Next Closest Time 🔒 |
Medium (46.58%) |
string |
cpp |
| 0682.Baseball Game |
Easy (76.06%) |
stack |
cpp |
| 0683.K Empty Slots 🔒 |
Hard (37.04%) |
ordered-set |
cpp |
| 0684.Redundant Connection |
Medium (62.78%) |
graph, tree, union-find, breadth-first-search, depth-first-search |
cpp |
| 0685.Redundant Connection II |
Hard (34.38%) |
graph, union-find, tree, hard |
cpp |
| 0686.Repeated String Match |
Medium (34.95%) |
string |
cpp |
| 0687.Longest Univalue Path |
Medium (41.41%) |
binary-tree, recursion |
cpp |
| 0688.Knight Probability in Chessboard |
Medium (56.15%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 0689.Maximum Sum of 3 Non-Overlapping Subarrays |
Hard (49.84%) |
prefix-sum, dyanmic-programming |
cpp |
| 0690.Employee Importance |
Medium (66.72%) |
hash-table, depth-first-search, breadth-first-search, graph |
cpp |
| 0691.Stickers to Spell Word |
Hard (48.29%) |
dynamic-programming, string, bit-manipulation |
cpp |
| 0692.Top K Frequent Words |
Medium (57.93%) |
hash-table, heap, ordered-set, sort, bucket-sort |
cpp |
| 0693.Binary Number with Alternating Bits |
Easy (62.34%) |
bit-manipulation |
cpp |
| 0694.Number of Distinct Islands 🔒 |
Medium (61.19%) |
depth-first-search, hash-table |
cpp |
| 0695.Max Area of Island |
Medium (71.93%) |
matrix, depth-first-search |
cpp |
| 0696.Count Binary Substrings |
Easy (65.54%) |
string, dynamic-programming |
cpp |
| 0697.Degree of an Array |
Easy (56.53%) |
array, hash-table |
cpp |
| 0698.Partition to K Equal Sum Subsets |
Medium (38.45%) |
depth-first-search, backtracking, sort |
cpp |
| 0699.Falling Squares |
Hard (44.88%) |
segment-tree, interval, ordered-map, hard |
cpp |
| 0700.Search in a Binary Search Tree |
Easy (79.55%) |
binary-search-tree, binary-tree, recursion |
cpp |
| 0701.Insert into a Binary Search Tree |
Medium (73.77%) |
binary-search-tree, binary-tree, recursion |
cpp |
| 0702.Search in a Sorted Array of Unknown Size 🔒 |
Medium (72.07%) |
binary-search, array |
cpp |
| 0703.Kth Largest Element in a Stream |
Easy (56.75%) |
heap, design |
cpp |
| 0704.Binary Search |
Easy (57.39%) |
binary-search |
cpp |
| 0705.Design HashSet |
Easy (66.91%) |
design, hash-table, array, linked-list, bit-manipulation |
cpp |
| 0706.Design HashMap |
Easy (65.66%) |
design, hash-table, array, linked-list |
cpp |
| 0707.Design Linked List |
Medium (28.15%) |
design, linked-list |
cpp |
| 0708.Insert into a Sorted Circular Linked List 🔒 |
Medium (35.96%) |
linked-list |
cpp |
| 0709.To Lower Case |
Easy (83.27%) |
string, easy |
cpp |
| 0710.Random Pick with Blacklist |
Hard (33.42%) |
array, hash-table, random |
cpp |
| 0711.Number of Distinct Islands II 🔒 |
Hard (52.92%) |
sort, hash-table, depth-first-search, geometry |
cpp |
| 0712.Minimum ASCII Delete Sum for Two Strings |
Medium (65.05%) |
dynamic-programming, string |
cpp |
| 0713.Subarray Product Less Than K |
Medium (51.27%) |
array, sliding-window |
cpp |
| 0714.Best Time to Buy and Sell Stock with Transaction Fee |
Medium (68.44%) |
array, dynamic-programming, depth-first-search, memoization |
cpp |
| 0715.Range Module |
Hard (44.17%) |
segment-tree, ordered-map, interval, hard, design |
cpp |
| 0716.Max Stack 🔒 |
Hard (45.03%) |
design, stack, linked-list, ordered-map |
cpp |
| 0717.1-bit and 2-bit Characters |
Easy (45.26%) |
array, dynamic-programming |
cpp |
| 0718.Maximum Length of Repeated Subarray |
Medium (50.96%) |
array, dynamic-programming |
cpp |
| 0719.Find K-th Smallest Pair Distance |
Hard (37.83%) |
sort, binary-search, two-pointers, sliding-window |
cpp |
| 0720.Longest Word in Dictionary |
Medium (52.34%) |
string, trie, hash-table, sort, greedy, depth-first-search, breadth-first-search |
cpp |
| 0721.Accounts Merge |
Medium (57.05%) |
breadth-first-search, union-find |
cpp |
| 0722.Remove Comments |
Medium (38.54%) |
string |
cpp |
| 0723.Candy Crush 🔒 |
Medium (76.89%) |
matrix, design, two-pointers |
cpp |
| 0724.Find Pivot Index |
Easy (57.37%) |
prefix-sum, math, array |
cpp |
| 0725.Split Linked List in Parts |
Medium (64.00%) |
linked-list |
cpp |
| 0726.Number of Atoms |
Hard (52.76%) |
hash-table, stack |
cpp |
| 0727.Minimum Window Subsequence 🔒 |
Hard (43.38%) |
string, dynamic-programming |
cpp |
| 0728.Self Dividing Numbers |
Easy (78.48%) |
math, easy |
cpp |
| 0729.My Calendar I |
Medium (56.55%) |
array, interval, ordered-map, binary-search |
cpp |
| 0730.Count Different Palindromic Subsequences |
Hard (45.30%) |
string, dynamic-programming, palindrome, hard |
cpp |
| 0731.My Calendar II |
Medium (55.35%) |
interval, ordered-map, difference-array, segment-tree |
cpp |
| 0732.My Calendar III |
Hard (71.57%) |
interval, ordered-map, difference-array, segment-tree |
cpp |
| 0733.Flood Fill |
Easy (63.78%) |
matrix, depth-first-search |
cpp |
| 0734.Sentence Similarity 🔒 |
Easy (44.26%) |
array, hash-table, string |
cpp |
| 0735.Asteroid Collision |
Medium (44.53%) |
stack |
cpp |
| 0736.Parse Lisp Expression |
Hard (51.70%) |
string, hash-table, recursion, stack |
cpp |
| 0737.Sentence Similarity II 🔒 |
Medium (49.87%) |
union-find, string, graph |
cpp |
| 0738.Monotone Increasing Digits |
Medium (47.94%) |
greedy, string |
cpp |
| 0739.Daily Temperatures |
Medium (65.98%) |
array, stack, monotonic-stack |
cpp |
| 0740.Delete and Earn |
Medium (56.49%) |
dynamic-programming |
cpp |
| 0741.Cherry Pickup |
Hard (36.72%) |
dynamic-programming, matrix, hard |
cpp |
| 0742.Closest Leaf in a Binary Tree 🔒 |
Medium (46.17%) |
graph, binary-tree, breadth-first-search, depth-first-search |
cpp |
| 0743.Network Delay Time |
Medium (53.61%) |
graph, dijkstra, heap, shortest-path |
cpp |
| 0744.Find Smallest Letter Greater Than Target |
Easy (51.95%) |
binary-search |
cpp |
| 0745.Prefix and Suffix Search |
Hard (41.03%) |
hash-table, string |
cpp |
| 0746.Min Cost Climbing Stairs |
Easy (65.57%) |
dynamic-programming, memoization, depth-first-search |
cpp |
| 0747.Largest Number At Least Twice of Others |
Easy (48.74%) |
array |
cpp |
| 0748.Shortest Completing Word |
Easy (59.85%) |
hash-table, string |
cpp |
| 0749.Contain Virus |
Hard (50.84%) |
breadth-first-search, hash-table, greedy, hard |
cpp |
| 0750.Number Of Corner Rectangles 🔒 |
Medium (67.69%) |
hash-table, matrix |
cpp |
| 0751.IP to CIDR 🔒 |
Medium (55.06%) |
bit-manipulation, greedy |
cpp |
| 0752.Open the Lock |
Medium (56.02%) |
breadth-first-search, hash-table |
cpp |
| 0753.Cracking the Safe |
Hard (56.75%) |
hash-table, graph, greedy |
cpp |
| 0754.Reach a Number |
Medium (42.99%) |
math |
cpp |
| 0755.Pour Water 🔒 |
Medium (46.79%) |
array |
cpp |
| 0756.Pyramid Transition Matrix |
Medium (52.65%) |
depth-first-search, memoization |
cpp |
| 0757.Set Intersection Size At Least Two |
Hard (44.35%) |
sort, greedy, array, interval |
cpp |
| 0758.Bold Words in String 🔒 |
Medium (51.40%) |
string, trie |
cpp |
| 0759.Employee Free Time 🔒 |
Hard (72.07%) |
sort, array, interval |
cpp |
| 0760.Find Anagram Mappings 🔒 |
Easy (83.61%) |
array |
cpp |
| 0761.Special Binary String |
Hard (61.02%) |
sort, recursion |
cpp |
| 0762.Prime Number of Set Bits in Binary Representation |
Easy (69.32%) |
bit-manipulation |
cpp |
| 0763.Partition Labels |
Medium (79.82%) |
string, greedy, string |
cpp |
| 0764.Largest Plus Sign |
Medium (48.17%) |
matrix |
cpp |
| 0765.Couples Holding Hands |
Hard (57.17%) |
union-find, greedy, graph |
cpp |
| 0766.Toeplitz Matrix |
Easy (68.92%) |
matrix |
cpp |
| 0767.Reorganize String |
Medium (54.53%) |
greedy, hash-table |
cpp |
| 0768.Max Chunks To Make Sorted II |
Hard (53.18%) |
sort, monotonic-stack, stack, array |
cpp |
| 0769.Max Chunks To Make Sorted |
Medium (58.36%) |
greedy, array |
cpp |
| 0770.Basic Calculator IV |
Hard (55.31%) |
string, basic-calculator, stack, math, arithmetic |
cpp |
| 0771.Jewels and Stones |
Easy (88.53%) |
hash-table |
cpp |
| 0772.Basic Calculator III 🔒 |
Hard (50.49%) |
string, basic-calculator, stack, math, arithmetic |
cpp |
| 0773.Sliding Puzzle |
Hard (64.68%) |
breadth-first-search, hash-table |
cpp |
| 0774.Minimize Max Distance to Gas Station 🔒 |
Hard (52.22%) |
binary-search |
cpp |
| 0775.Global and Local Inversions |
Medium (42.46%) |
array, sort, math |
cpp |
| 0776.Split BST 🔒 |
Medium (82.80%) |
binary-search-tree, binary-tree |
cpp |
| 0777.Swap Adjacent in LR String |
Medium (36.80%) |
string, two-pointers |
cpp |
| 0778.Swim in Rising Water |
Hard (60.64%) |
matrix, heap, breadth-first search |
cpp |
| 0779.K-th Symbol in Grammar |
Medium (46.44%) |
array, binary-tree, recursion |
cpp |
| 0780.Reaching Points |
Hard (33.14%) |
array, math |
cpp |
| 0781.Rabbits in Forest |
Medium (53.39%) |
hash-table, array |
cpp |
| 0782.Transform to Chessboard |
Hard (50.90%) |
hard, matrix |
cpp |
| 0783.Minimum Distance Between BST Nodes |
Easy (59.53%) |
binary-search-tree, binary-tree |
cpp |
| 0784.Letter Case Permutation |
Medium (74.14%) |
permutation, bit-manipulation, backtracking |
cpp |
| 0785.Is Graph Bipartite? |
Medium (55.55%) |
graph, breadth-first-search, depth-first-search, union-find |
cpp |
| 0786.K-th Smallest Prime Fraction |
Medium (53.76%) |
binary-search, heap, two-pointers, array |
cpp |
| 0787.Cheapest Flights Within K Stops |
Medium (39.27%) |
graph, bellman-ford, memoization, depth-first-search, shortest-path |
cpp |
| 0788.Rotated Digits |
Medium (56.41%) |
math, dynamic-programming |
cpp |
| 0789.Escape The Ghosts |
Medium (61.68%) |
geometry, math |
cpp |
| 0790.Domino and Tromino Tiling |
Medium (50.71%) |
array, dynamic-programming |
cpp |
| 0791.Custom Sort String |
Medium (70.59%) |
string, hash-table, sort |
cpp |
| 0792.Number of Matching Subsequences |
Medium (51.08%) |
binary-search, hash-table, string |
cpp |
| 0793.Preimage Size of Factorial Zeroes Function |
Hard (44.17%) |
math, binary-search |
cpp |
| 0794.Valid Tic-Tac-Toe State |
Medium (34.76%) |
array |
cpp |
| 0795.Number of Subarrays with Bounded Maximum |
Medium (53.12%) |
array, sliding-window, math |
cpp |
| 0796.Rotate String |
Easy (57.94%) |
string, kmp |
cpp |
| 0797.All Paths From Source to Target |
Medium (82.41%) |
graph, breadth-first-search, depth-first-search |
cpp |
| 0798.Smallest Rotation with Highest Score |
Hard (51.08%) |
difference-array, array, math, hard |
cpp |
| 0799.Champagne Tower |
Medium (58.10%) |
array |
cpp |
| 0800.Similar RGB Color 🔒 |
Easy (67.36%) |
string |
cpp |
| 0801.Minimum Swaps To Make Sequences Increasing |
Hard (39.86%) |
dynamic-programming, array |
cpp |
| 0802.Find Eventual Safe States |
Medium (62.35%) |
depth-first-search, graph, topological-sort |
cpp |
| 0803.Bricks Falling When Hit |
Hard (34.69%) |
depth-first-search, union-find, matrix, hash-table, hard |
cpp |
| 0804.Unique Morse Code Words |
Easy (82.81%) |
string, hash-table, easy |
cpp |
| 0805.Split Array With Same Average |
Hard (25.38%) |
math, bit-manipulation, hard |
cpp |
| 0806.Number of Lines To Write String |
Easy (68.15%) |
string, easy |
cpp |
| 0807.Max Increase to Keep City Skyline |
Medium (86.08%) |
geometry |
cpp |
| 0808.Soup Servings |
Medium (54.05%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 0809.Expressive Words |
Medium (46.10%) |
two-pointers, string |
cpp |
| 0810.Chalkboard XOR Game |
Hard (59.13%) |
math, game-theory |
cpp |
| 0811.Subdomain Visit Count |
Medium (76.13%) |
hash-table, string |
cpp |
| 0812.Largest Triangle Area |
Easy (60.43%) |
math, geometry |
cpp |
| 0813.Largest Sum of Averages |
Medium (53.43%) |
dynamic-programming, recursion, memoization, array |
cpp |
| 0814.Binary Tree Pruning |
Medium (72.17%) |
binary-tree, depth-first-search |
cpp |
| 0815.Bus Routes |
Hard (47.97%) |
breadth-first-search |
cpp |
| 0816.Ambiguous Coordinates |
Medium (56.68%) |
string |
cpp |
| 0817.Linked List Components |
Medium (56.84%) |
hash-table, linked-list |
cpp |
| 0818.Race Car |
Hard (43.60%) |
math, bit-manipulation, breadth-first-search, dynamic-programming, hash-table |
cpp |
| 0819.Most Common Word |
Easy (44.35%) |
hash-table, string |
cpp |
| 0820.Short Encoding of Words |
Medium (60.44%) |
hash-table, string, sort |
cpp |
| 0821.Shortest Distance to a Character |
Easy (71.51%) |
array |
cpp |
| 0822.Card Flipping Game |
Medium (47.19%) |
hash-table, array |
cpp |
| 0823.Binary Trees With Factors |
Medium (52.92%) |
math, dynamic-programming, binary-tree |
cpp |
| 0824.Goat Latin |
Easy (68.12%) |
string |
cpp |
| 0825.Friends Of Appropriate Ages |
Medium (47.35%) |
array, prefix-sum |
cpp |
| 0826.Most Profit Assigning Work |
Medium (46.23%) |
dynamic-programming, greedy |
cpp |
| 0827.Making A Large Island |
Hard (47.01%) |
matrix, union-find |
cpp |
| 0828.Count Unique Characters of All Substrings of a Given String |
Hard (52.28%) |
hash-table, math, string |
cpp |
| 0829.Consecutive Numbers Sum |
Hard (41.81%) |
array, math |
cpp |
| 0830.Positions of Large Groups |
Easy (52.19%) |
string, two-pointers |
cpp |
| 0831.Masking Personal Information |
Medium (48.53%) |
string |
cpp |
| 0832.Flipping an Image |
Easy (81.79%) |
matrix, bit-manipulation |
cpp |
| 0833.Find And Replace in String |
Medium (52.77%) |
string, hash-table |
cpp |
| 0834.Sum of Distances in Tree |
Hard (59.30%) |
graph, tree, depth-first-search |
cpp |
| 0835.Image Overlap |
Medium (63.65%) |
matrix, hash-table |
cpp |
| 0836.Rectangle Overlap |
Easy (44.70%) |
geometry, math |
cpp |
| 0837.New 21 Game |
Medium (45.01%) |
math, depth-first-search, memoization, hard |
cpp |
| 0838.Push Dominoes |
Medium (57.10%) |
array |
cpp |
| 0839.Similar String Groups |
Hard (54.81%) |
string, union-find |
cpp |
| 0840.Magic Squares In Grid |
Medium (38.93%) |
matrix |
cpp |
| 0841.Keys and Rooms |
Medium (72.86%) |
graph, depth-first-search, breadth-first-search |
cpp |
| 0842.Split Array into Fibonacci Sequence |
Medium (39.02%) |
backtracking, string |
cpp |
| 0843.Guess the Word |
Hard (39.45%) |
game |
cpp |
| 0844.Backspace String Compare |
Easy (49.13%) |
stack, string, two-pointers |
cpp |
| 0845.Longest Mountain in Array |
Medium (40.28%) |
array |
cpp |
| 0846.Hand of Straights |
Medium (55.82%) |
ordered-map, array |
cpp |
| 0847.Shortest Path Visiting All Nodes |
Hard (65.54%) |
bit-manipulation, breadth-first-search, heap, hash-table |
cpp |
| 0848.Shifting Letters |
Medium (44.77%) |
prefix-sum |
cpp |
| 0849.Maximize Distance to Closest Person |
Medium (48.05%) |
array |
cpp |
| 0850.Rectangle Area II |
Hard (54.12%) |
line-sweep, segment-tree, hard |
cpp |
| 0851.Loud and Rich |
Medium (59.19%) |
graph, depth-first-search |
cpp |
| 0852.Peak Index in a Mountain Array |
Medium (68.45%) |
array, binary-search |
cpp |
| 0853.Car Fleet |
Medium (50.88%) |
sort, greedy, ordered-map, heap |
cpp |
| 0854.K-Similar Strings |
Hard (39.78%) |
breadth-first-search, string |
cpp |
| 0855.Exam Room |
Medium (43.28%) |
ordered-set, unordered-map, sort, interval, design |
cpp |
| 0856.Score of Parentheses |
Medium (64.21%) |
stack, string, parentheses |
cpp |
| 0857.Minimum Cost to Hire K Workers |
Hard (52.89%) |
array, heap, greedy |
cpp |
| 0858.Mirror Reflection |
Medium (62.68%) |
math, greatest-common-divisor |
cpp |
| 0859.Buddy Strings |
Easy (33.07%) |
string |
cpp |
| 0860.Lemonade Change |
Easy (53.21%) |
greedy |
cpp |
| 0861.Score After Flipping Matrix |
Medium (74.92%) |
greedy |
cpp |
| 0862.Shortest Subarray with Sum at Least K |
Hard (26.00%) |
array, prefix-sum, monotonic-queue, hard |
cpp |
| 0863.All Nodes Distance K in Binary Tree |
Medium (64.36%) |
binary-tree, depth-first-search, breadth-first-search, hash-table |
cpp |
| 0864.Shortest Path to Get All Keys |
Hard (53.77%) |
bit-manipulation, breadth-first-search |
cpp |
| 0865.Smallest Subtree with all the Deepest Nodes |
Medium (70.47%) |
binary-tree |
cpp |
| 0866.Prime Palindrome |
Medium (25.92%) |
palindrome, prime, math |
cpp |
| 0867.Transpose Matrix |
Easy (71.29%) |
easy |
cpp |
| 0868.Binary Gap |
Easy (63.26%) |
bit-manipulation |
cpp |
| 0869.Reordered Power of 2 |
Medium (62.77%) |
math |
cpp |
| 0870.Advantage Shuffle |
Medium (52.45%) |
array, sort, greedy, heap |
cpp |
| 0871.Minimum Number of Refueling Stops |
Hard (40.03%) |
dynamic-programming, heap |
cpp |
| 0872.Leaf-Similar Trees |
Easy (70.21%) |
binary-tree, depth-first-search |
cpp |
| 0873.Length of Longest Fibonacci Subsequence |
Medium (48.41%) |
array, dynamic-programming, hash-table |
cpp |
| 0874.Walking Robot Simulation |
Medium (39.92%) |
hash-table |
cpp |
| 0875.Koko Eating Bananas |
Medium (48.91%) |
binary-search |
cpp |
| 0876.Middle of the Linked List |
Easy (78.33%) |
linked-list, fast-slow-pointers |
cpp |
| 0877.Stone Game |
Medium (70.54%) |
dynamic-programming, minmax, math |
cpp |
| 0878.Nth Magical Number |
Hard (35.37%) |
math, binary-search |
cpp |
| 0879.Profitable Schemes |
Hard (48.39%) |
array, dynamic-programming |
cpp |
| 0880.Decoded String at Index |
Medium (36.42%) |
string |
cpp |
| 0881.Boats to Save People |
Medium (56.62%) |
greedy, two-pointers |
cpp |
| 0882.Reachable Nodes In Subdivided Graph |
Hard (50.19%) |
graph, dijkstra, shortest-path |
cpp |
| 0883.Projection Area of 3D Shapes |
Easy (72.40%) |
geometry, math |
cpp |
| 0884.Uncommon Words from Two Sentences |
Easy (67.19%) |
hash-table, string |
cpp |
| 0885.Spiral Matrix III |
Medium (74.36%) |
matrix |
cpp |
| 0886.Possible Bipartition |
Medium (50.52%) |
graph, union-find |
cpp |
| 0887.Super Egg Drop |
Hard (27.62%) |
memoization, depth-first-search, binary-search |
cpp |
| 0888.Fair Candy Swap |
Easy (61.58%) |
hash-table |
cpp |
| 0889.Construct Binary Tree from Preorder and Postorder Traversal |
Medium (71.34%) |
binary-tree, hash-table, recursion |
cpp |
| 0890.Find and Replace Pattern |
Medium (76.88%) |
hash-table, string |
cpp |
| 0891.Sum of Subsequence Widths |
Hard (37.73%) |
math, sort |
cpp |
| 0892.Surface Area of 3D Shapes |
Easy (65.69%) |
geometry |
cpp |
| 0893.Groups of Special-Equivalent Strings |
Medium (71.59%) |
hash-table, string |
cpp |
| 0894.All Possible Full Binary Trees |
Medium (82.70%) |
binary-tree, hash-table, recursion |
cpp |
| 0895.Maximum Frequency Stack |
Hard (66.48%) |
heap, hash-table, design |
cpp |
| 0896.Monotonic Array |
Easy (61.11%) |
array, easy |
cpp |
| 0897.Increasing Order Search Tree |
Easy (78.27%) |
binary-tree, binary-search-tree |
cpp |
| 0898.Bitwise ORs of Subarrays |
Medium (38.52%) |
array, hash-table |
cpp |
| 0899.Orderly Queue |
Hard (65.95%) |
math, string |
cpp |
| 0900.RLE Iterator |
Medium (59.46%) |
design, string |
cpp |
| 0901.Online Stock Span |
Medium (65.75%) |
array, monotonic-stack |
cpp |
| 0902.Numbers At Most N Given Digit Set |
Hard (42.37%) |
depth-first-search, memoization, digit, string, hard |
cpp |
| 0903.Valid Permutations for DI Sequence |
Hard (57.41%) |
dynamic-programming, array |
cpp |
| 0904.Fruit Into Baskets |
Medium (44.14%) |
hash-table, sliding-window |
cpp |
| 0905.Sort Array By Parity |
Easy (76.22%) |
array, two-pointers, partition |
cpp |
| 0906.Super Palindromes |
Hard (38.85%) |
palindrome, math, string |
cpp |
| 0907.Sum of Subarray Minimums |
Medium (37.41%) |
array, monotonic-stack, dynamic-programming, stack, math |
cpp |
| 0908.Smallest Range I |
Easy (69.86%) |
math |
cpp |
| 0909.Snakes and Ladders |
Medium (43.81%) |
breadth-first-search |
cpp |
| 0910.Smallest Range II |
Medium (36.18%) |
math, sort |
cpp |
| 0911.Online Election |
Medium (51.96%) |
binary-search, hash-table |
cpp |
| 0912.Sort an Array |
Medium (56.68%) |
sort, TODO |
cpp |
| 0913.Cat and Mouse |
Hard (34.07%) |
breadth-first search, graph, queue, minimax, game-theory, hard |
cpp |
| 0914.X of a Kind in a Deck of Cards |
Easy (30.02%) |
math |
cpp |
| 0915.Partition Array into Disjoint Intervals |
Medium (48.77%) |
array |
cpp |
| 0916.Word Subsets |
Medium (52.30%) |
hash-table, string |
cpp |
| 0917.Reverse Only Letters |
Easy (64.33%) |
string, two-pointers |
cpp |
| 0918.Maximum Sum Circular Subarray |
Medium (44.67%) |
dynamic-programming, array, prefix-sum |
cpp |
| 0919.Complete Binary Tree Inserter |
Medium (65.43%) |
queue, array, binary-tree, design |
cpp |
| 0920.Number of Music Playlists |
Hard (60.54%) |
dynamic-programming |
cpp |
| 0921.Minimum Add to Make Parentheses Valid |
Medium (75.12%) |
string, parentheses, stack, greedy |
cpp |
| 0922.Sort Array By Parity II |
Easy (70.71%) |
array, two-pointers |
cpp |
| 0923.3Sum With Multiplicity |
Medium (45.40%) |
math, sort, two-pointers, hash-table, dynamic-programming |
cpp |
| 0924.Minimize Malware Spread |
Hard (42.00%) |
breadth-first-search, union-find, graph |
cpp |
| 0925.Long Pressed Name |
Easy (32.35%) |
string, two-pointers |
cpp |
| 0926.Flip String to Monotone Increasing |
Medium (61.40%) |
string |
cpp |
| 0927.Three Equal Parts |
Hard (39.75%) |
array, bit-manipulation, math |
cpp |
| 0928.Minimize Malware Spread II |
Hard (43.41%) |
union-find, graph, breadth-first-search |
cpp |
| 0929.Unique Email Addresses |
Easy (67.12%) |
string, hash-table |
cpp |
| 0930.Binary Subarrays With Sum |
Medium (62.06%) |
array, prefix-sum, hash-table, sliding-window |
cpp |
| 0931.Minimum Falling Path Sum |
Medium (64.44%) |
dynamic-programming |
cpp |
| 0932.Beautiful Array |
Medium (65.65%) |
array, divide-and-conquer, math |
cpp |
| 0933.Number of Recent Calls |
Easy (74.93%) |
queue, binary-search |
cpp |
| 0934.Shortest Bridge |
Medium (57.68%) |
depth-first-search, breadth-first-search |
cpp |
| 0935.Knight Dialer |
Medium (59.99%) |
math, dynamic-programming, matrix |
cpp |
| 0936.Stamping The Sequence |
Hard (62.49%) |
greedy, string |
cpp |
| 0937.Reorder Data in Log Files |
Medium (56.40%) |
string, sort |
cpp |
| 0938.Range Sum of BST |
Easy (86.79%) |
binary-search-tree, binary-tree, depth-first-search |
cpp |
| 0939.Minimum Area Rectangle |
Medium (53.53%) |
ordered-map, hash-table, sort |
cpp |
| 0940.Distinct Subsequences II |
Hard (43.15%) |
dynamic-programming, string |
cpp |
| 0941.Valid Mountain Array |
Easy (33.40%) |
array |
cpp |
| 0942.DI String Match |
Easy (78.45%) |
two-pointers |
cpp |
| 0943.Find the Shortest Superstring |
Hard (43.79%) |
string, dynamic-programming, bit-manipulation |
cpp |
| 0944.Delete Columns to Make Sorted |
Easy (74.56%) |
string, easy |
cpp |
| 0945.Minimum Increment to Make Array Unique |
Medium (52.38%) |
sort, greedy |
cpp |
| 0946.Validate Stack Sequences |
Medium (69.44%) |
stack |
cpp |
| 0947.Most Stones Removed with Same Row or Column |
Medium (58.83%) |
union-find |
cpp |
| 0948.Bag of Tokens |
Medium (58.92%) |
greedy |
cpp |
| 0949.Largest Time for Given Digits |
Medium (35.13%) |
easy |
cpp |
| 0950.Reveal Cards In Increasing Order |
Medium (82.86%) |
sort, array, queue |
cpp |
| 0951.Flip Equivalent Binary Trees |
Medium (66.92%) |
binary-tree, depth-first-search |
cpp |
| 0952.Largest Component Size by Common Factor |
Hard (40.53%) |
union-find, graph, math |
cpp |
| 0953.Verifying an Alien Dictionary |
Easy (54.92%) |
string, hash-table |
cpp |
| 0954.Array of Doubled Pairs |
Medium (39.13%) |
sort, hash-table, ordered-map |
cpp |
| 0955.Delete Columns to Make Sorted II |
Medium (35.13%) |
greedy, string |
cpp |
| 0956.Tallest Billboard |
Hard (52.35%) |
dynamic-programming |
cpp |
| 0957.Prison Cells After N Days |
Medium (38.94%) |
hash-table |
cpp |
| 0958.Check Completeness of a Binary Tree |
Medium (56.78%) |
binary-tree, breadth-first-search |
cpp |
| 0959.Regions Cut By Slashes |
Medium (69.33%) |
depth-first-search |
cpp |
| 0960.Delete Columns to Make Sorted III |
Hard (57.82%) |
dynamic-programming, string |
cpp |
| 0961.N-Repeated Element in Size 2N Array |
Easy (76.60%) |
hash-table, math |
cpp |
| 0962.Maximum Width Ramp |
Medium (49.83%) |
array, stack, monotonic-stack |
cpp |
| 0963.Minimum Area Rectangle II |
Medium (54.71%) |
math, geometry, hash-table |
cpp |
| 0964.Least Operators to Express Number |
Hard (48.36%) |
hard, digit, arithmetic |
cpp |
| 0965.Univalued Binary Tree |
Easy (70.73%) |
binary-tree, depth-first-search |
cpp |
| 0966.Vowel Spellchecker |
Medium (51.37%) |
hash-table, string |
cpp |
| 0967.Numbers With Same Consecutive Differences |
Medium (57.97%) |
recursion, math |
cpp |
| 0968.Binary Tree Cameras |
Hard (46.59%) |
binary-tree, depth-first-search |
cpp |
| 0969.Pancake Sorting |
Medium (70.60%) |
array, sort, greedy |
cpp |
| 0970.Powerful Integers |
Medium (43.75%) |
math, hash-table |
cpp |
| 0971.Flip Binary Tree To Match Preorder Traversal |
Medium (50.46%) |
binary-tree, depth-first-search |
cpp |
| 0972.Equal Rational Numbers |
Hard (43.77%) |
math, string |
cpp |
| 0973.K Closest Points to Origin |
Medium (66.27%) |
sort, heap |
cpp |
| 0974.Subarray Sums Divisible by K |
Medium (53.99%) |
hash-table, prefix-sum, math |
cpp |
| 0975.Odd Even Jump |
Hard (39.75%) |
ordered-map, depth-first-search, memoization, array |
cpp |
| 0976.Largest Perimeter Triangle |
Easy (55.89%) |
array, sort, greedy |
cpp |
| 0977.Squares of a Sorted Array |
Easy (72.82%) |
array, two-pointers |
cpp |
| 0978.Longest Turbulent Subarray |
Medium (47.32%) |
array, dynamic-programming |
cpp |
| 0979.Distribute Coins in Binary Tree |
Medium (72.57%) |
binary-tree, depth-first-search |
cpp |
| 0980.Unique Paths III |
Hard (81.71%) |
depth-first-search |
cpp |
| 0981.Time Based Key-Value Store |
Medium (49.47%) |
hash-table, binary-search, design, ordered-map |
cpp |
| 0982.Triples with Bitwise AND Equal To Zero |
Hard (58.03%) |
array, hash-table |
cpp |
| 0983.Minimum Cost For Tickets |
Medium (65.28%) |
dynamic-programming |
cpp |
| 0984.String Without AAA or BBB |
Medium (43.82%) |
greedy, string, recursion |
cpp |
| 0985.Sum of Even Numbers After Queries |
Medium (68.06%) |
array |
cpp |
| 0986.Interval List Intersections |
Medium (71.56%) |
two-pointers, interval |
cpp |
| 0987.Vertical Order Traversal of a Binary Tree |
Hard (47.36%) |
depth-first-search, sort, binary-tree |
cpp |
| 0988.Smallest String Starting From Leaf |
Medium (51.17%) |
binary-tree, depth-first-search |
cpp |
| 0989.Add to Array-Form of Integer |
Easy (45.44%) |
array, arithmetic |
cpp |
| 0990.Satisfiability of Equality Equations |
Medium (50.45%) |
depth-first-search, union-find, graph, math |
cpp |
| 0991.Broken Calculator |
Medium (54.36%) |
math, greedy, recursion |
cpp |
| 0992.Subarrays with K Different Integers |
Hard (62.96%) |
sliding-window, array, hash-table |
cpp |
| 0993.Cousins in Binary Tree |
Easy (55.89%) |
binary-tree, breadth-first-search, depth-first-search |
cpp |
| 0994.Rotting Oranges |
Medium (53.97%) |
matrix, breadth-first-search |
cpp |
| 0995.Minimum Number of K Consecutive Bit Flips |
Hard (51.53%) |
greedy, array, difference-array, bit-manipulation |
cpp |
| 0996.Number of Squareful Arrays |
Hard (50.07%) |
array, permutation, recursion, sort, hash-table |
cpp |
| 0997.Find the Town Judge |
Easy (49.79%) |
graph |
cpp |
| 0998.Maximum Binary Tree II |
Medium (68.94%) |
binary-tree, recursion |
cpp |
| 0999.Available Captures for Rook |
Easy (68.85%) |
depth-first-search, matrix |
cpp |
| 1000.Minimum Cost to Merge Stones |
Hard (42.99%) |
prefix-sum, dynamic-programming, hard |
cpp |
| 1001.Grid Illumination |
Hard (36.64%) |
hash-table, matrix |
cpp |
| 1002.Find Common Characters |
Easy (68.86%) |
array, string, hash-table |
cpp |
| 1003.Check If Word Is Valid After Substitutions |
Medium (59.41%) |
stack, string |
cpp |
| 1004.Max Consecutive Ones III |
Medium (62.85%) |
sliding-window |
cpp |
| 1005.Maximize Sum Of Array After K Negations |
Easy (51.03%) |
array, greedy, sort |
cpp |
| 1006.Clumsy Factorial |
Medium (56.89%) |
stack, math |
cpp |
| 1007.Minimum Domino Rotations For Equal Row |
Medium (52.20%) |
array, greedy |
cpp |
| 1008.Construct Binary Search Tree from Preorder Traversal |
Medium (81.88%) |
binary-tree, binary-search-tree, depth-first-search |
cpp |
| 1009.Complement of Base 10 Integer |
Easy (60.78%) |
bit-manipulation |
cpp |
| 1010.Pairs of Songs With Total Durations Divisible by 60 |
Medium (52.86%) |
array, hash-table |
cpp |
| 1011.Capacity To Ship Packages Within D Days |
Medium (69.29%) |
array, binary-search |
cpp |
| 1012.Numbers With Repeated Digits |
Hard (42.01%) |
math, hash-table, digit |
cpp |
| 1013.Partition Array Into Three Parts With Equal Sum |
Easy (41.98%) |
array, prefix-sum |
cpp |
| 1014.Best Sightseeing Pair |
Medium (59.23%) |
array |
cpp |
| 1015.Smallest Integer Divisible by K |
Medium (46.65%) |
math |
cpp |
| 1016.Binary String With Substrings Representing 1 To N |
Medium (57.37%) |
bit-manipulation, math, string |
cpp |
| 1017.Convert to Base -2 |
Medium (60.58%) |
math |
cpp |
| 1018.Binary Prefix Divisible By 5 |
Easy (46.72%) |
math |
cpp |
| 1019.Next Greater Node In Linked List |
Medium (60.67%) |
linked-list, stack, monotonic-stack |
cpp |
| 1020.Number of Enclaves |
Medium (68.72%) |
depth-first-search, breadth-first-search, union-find, matrix, graph |
cpp |
| 1021.Remove Outermost Parentheses |
Easy (82.41%) |
parentheses, stack, string |
cpp |
| 1022.Sum of Root To Leaf Binary Numbers |
Easy (73.07%) |
binary-tree, depth-first-search |
cpp |
| 1023.Camelcase Matching |
Medium (62.12%) |
string |
cpp |
| 1024.Video Stitching |
Medium (51.33%) |
dynamic-programming, greedy, interval |
cpp |
| 1025.Divisor Game |
Easy (68.61%) |
math, game-theory |
cpp |
| 1026.Maximum Difference Between Node and Ancestor |
Medium (78.14%) |
binary-tree, depth-first-search |
cpp |
| 1027.Longest Arithmetic Subsequence |
Medium (49.03%) |
dynamic-programming |
cpp |
| 1028.Recover a Tree From Preorder Traversal |
Hard (74.19%) |
binary-tree, depth-first-search, string |
cpp |
| 1029.Two City Scheduling |
Medium (66.63%) |
greedy |
cpp |
| 1030.Matrix Cells in Distance Order |
Easy (70.94%) |
breadth-first-search, sort |
cpp |
| 1031.Maximum Sum of Two Non-Overlapping Subarrays |
Medium (59.74%) |
array, prefix-sum |
cpp |
| 1032.Stream of Characters |
Hard (51.91%) |
trie, design |
cpp |
| 1033.Moving Stones Until Consecutive |
Medium (47.80%) |
greedy, math |
cpp |
| 1034.Coloring A Border |
Medium (48.89%) |
depth-first-search, matrix |
cpp |
| 1035.Uncrossed Lines |
Medium (62.92%) |
dynamic-programming |
cpp |
| 1036.Escape a Large Maze |
Hard (34.86%) |
hash-table, math, matrix, breadth-first-search |
cpp |
| 1037.Valid Boomerang |
Easy (36.95%) |
math, geometry |
cpp |
| 1038.Binary Search Tree to Greater Sum Tree |
Medium (85.79%) |
binary-search-tree, binary-tree |
cpp |
| 1039.Minimum Score Triangulation of Polygon |
Medium (58.71%) |
dynamic-programming, memoization, depth-first-search, geometry, math |
cpp |
| 1040.Moving Stones Until Consecutive II |
Medium (56.76%) |
greedy, two-pointers |
cpp |
| 1041.Robot Bounded In Circle |
Medium (55.63%) |
array |
cpp |
| 1042.Flower Planting With No Adjacent |
Medium (51.18%) |
graph, greedy |
cpp |
| 1043.Partition Array for Maximum Sum |
Medium (76.44%) |
dynamic-programming |
cpp |
| 1044.Longest Duplicate Substring |
Hard (30.53%) |
string, hash-table, binary-search |
cpp |
| 1046.Last Stone Weight |
Easy (65.31%) |
heap |
cpp |
| 1047.Remove All Adjacent Duplicates In String |
Easy (69.42%) |
stack, string |
cpp |
| 1048.Longest String Chain |
Medium (61.00%) |
hash-table, sort |
cpp |
| 1049.Last Stone Weight II |
Medium (55.20%) |
dynamic-programming |
cpp |
| 1051.Height Checker |
Easy (76.46%) |
sort, counting-sort, array |
cpp |
| 1052.Grumpy Bookstore Owner |
Medium (57.08%) |
prefix-sum |
cpp |
| 1053.Previous Permutation With One Swap |
Medium (49.71%) |
math, permutation, greedy |
cpp |
| 1054.Distant Barcodes |
Medium (46.46%) |
hash-table, sort |
cpp |
| 1055.Shortest Way to Form String 🔒 |
Medium (60.09%) |
string, two-pointers |
cpp |
| 1056.Confusing Number 🔒 |
Easy (48.66%) |
math |
cpp |
| 1057.Campus Bikes 🔒 |
Medium (58.58%) |
sort, geometry |
cpp |
| 1058.Minimize Rounding Error to Meet Target 🔒 |
Medium (45.01%) |
math |
cpp |
| 1059.All Paths from Source Lead to Destination 🔒 |
Medium (37.67%) |
graph, depth-first-search, memoization |
cpp |
| 1060.Missing Element in Sorted Array 🔒 |
Medium (56.60%) |
array, binary-search |
cpp |
| 1061.Lexicographically Smallest Equivalent String |
Medium (76.49%) |
union-find, string |
cpp |
| 1062.Longest Repeating Substring 🔒 |
Medium (60.52%) |
dynamic-programming, string |
cpp |
| 1063.Number of Valid Subarrays 🔒 |
Hard (78.41%) |
array, monotonic-stack |
cpp |
| 1064.Fixed Point 🔒 |
Easy (64.14%) |
array, binary-search |
cpp |
| 1065.Index Pairs of a String 🔒 |
Easy (67.25%) |
string, trie |
cpp |
| 1066.Campus Bikes II 🔒 |
Medium (55.17%) |
dynamic-programming, geometry, math |
cpp |
| 1067.Digit Count in Range 🔒 |
Hard (46.44%) |
math |
cpp |
| 1071.Greatest Common Divisor of Strings |
Easy (51.43%) |
string |
cpp |
| 1072.Flip Columns For Maximum Number of Equal Rows |
Medium (63.82%) |
matrix, hash-table |
cpp |
| 1073.Adding Two Negabinary Numbers |
Medium (36.75%) |
arithmetic |
cpp |
| 1074.Number of Submatrices That Sum to Target |
Hard (74.42%) |
hash-table, prefix-sum, matrix |
cpp |
| 1078.Occurrences After Bigram |
Easy (63.42%) |
string |
cpp |
| 1079.Letter Tile Possibilities |
Medium (76.15%) |
hash-table, recursion, permutation, string |
cpp |
| 1080.Insufficient Nodes in Root to Leaf Paths |
Medium (55.30%) |
binary-tree, depth-first-search |
cpp |
| 1086.High Five 🔒 |
Easy (74.55%) |
array, sort |
cpp |
| 1091.Shortest Path in Binary Matrix |
Medium (47.21%) |
breadth-first-search, matrix |
cpp |
| 1140.Stone Game II |
Medium (67.91%) |
depth-first-search, memoization, minimax, game-theory, prefix-sum |
cpp |
| 1143.Longest Common Subsequence |
Medium (57.78%) |
dynamic-programming, string |
cpp |
| 1201.Ugly Number III |
Medium (29.35%) |
binary-search, math |
cpp |
| 1209.Remove All Adjacent Duplicates in String II |
Medium (57.62%) |
stack, string |
cpp |
| 1217.Minimum Cost to Move Chips to The Same Position |
Easy (71.70%) |
math |
cpp |
| 1268.Search Suggestions System |
Medium (65.21%) |
sort, trie, design |
cpp |
| 1276.Number of Burgers with No Waste of Ingredients |
Medium (51.06%) |
math |
cpp |
| 1277.Count Square Submatrices with All Ones |
Medium (75.03%) |
dynamic-programming, matrix |
cpp |
| 1283.Find the Smallest Divisor Given a Threshold |
Medium (59.38%) |
binary-search, array |
cpp |
| 1290.Convert Binary Number in a Linked List to Integer |
Easy (81.14%) |
linked-list, easy |
cpp |
| 1312.Minimum Insertion Steps to Make a String Palindrome |
Hard (70.36%) |
string, dynamic-programming, depth-first-search, memoization, palindrome |
cpp |
| 1332.Remove Palindromic Subsequences |
Easy (76.34%) |
string, palindrome, greedy |
cpp |
| 1334.Find the City With the Smallest Number of Neighbors at a Threshold Distance |
Medium (59.78%) |
graph, dijkstra, shortest-path |
cpp |
| 1340.Jump Game V |
Hard (63.14%) |
depth-first-search, memoization, array |
cpp |
| 1345.Jump Game IV |
Hard (46.26%) |
hash-table, breadth-first-search, array |
cpp |
| 1376.Time Needed to Inform All Employees |
Medium (60.01%) |
graph, tree, depth-first-search |
cpp |
| 1411.Number of Ways to Paint N × 3 Grid |
Hard (63.43%) |
math |
cpp |
| 1423.Maximum Points You Can Obtain from Cards |
Medium (52.47%) |
sliding-window, array |
cpp |
| 1429.First Unique Number 🔒 |
Medium (53.60%) |
queue, hash-table, design |
cpp |
| 1438.Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit |
Medium (49.24%) |
sliding-window, ordered-map |
cpp |
| 1446.Consecutive Characters |
Easy (60.40%) |
string, easy |
cpp |
| 1472.Design Browser History |
Medium (77.50%) |
stack, design |
cpp |
| 1510. Stone Game IV |
Hard (59.74%) |
dynamic-programming, game-theory |
cpp |
| 1600.Throne Inheritance |
Medium (64.91%) |
tree |
cpp |
| 1658.Minimum Operations to Reduce X to Zero |
Medium (39.67%) |
array, hash-table, prefix-sum |
cpp |
| 1706.Where Will the Ball Fall |
Medium (71.76%) |
dynamic-programming, depth-first-search, memoization |
cpp |
| 1971.Find if Path Exists in Graph |
Easy (51.57%) |
graph, depth-first-search, breadth-first-search, union-find |
cpp |
| 2296.Design a Text Editor |
Hard (44.05%) |
stack, string, design, linked-list |
cpp |
| 2401.Longest Nice Subarray |
Medium (50.75%) |
bit-manipulation, sliding-window |
cpp |
| 2423.Remove Letter To Equalize Frequency |
Easy (17.25%) |
hash-table, string |
cpp |
| 2462.Total Cost to Hire K Workers |
Medium (43.19%) |
heap, sort, greedy, two-pointers |
cpp |
| 2511.Maximum Enemy Forts That Can Be Captured |
Easy (38.02%) |
array, two-pointers |
cpp |