LeetCode 75 Study Plan Solutions

Solutions to the LeetCode 75 study plan problems, a curated list of 75 essential LeetCode problems for interview preparation. Implemented in Python 3.10+. Each file is self‑documenting, runnable, and named so problems sort naturally.

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About LeetCode 75

LeetCode 75 is a curated study plan by LeetCode that covers 75 essential problems across various topics including arrays, strings, linked lists, trees, dynamic programming, and more to help you prepare for coding interviews.

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Progress

Completed: 31/75

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Overview

Purpose: Store and run LeetCode solutions for practice.
Language: Python 3.10+
Tested with: Python 3.10.6

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Problems Solved

#	Problem	Difficulty	Solution
605	Can Place Flowers	Easy	605_can_place_flowers.py
1071	Greatest Common Divisor of Strings	Easy	1071_greatest_common_divisor_of_strings.py
1431	Kids With the Greatest Number of Candies	Easy	1431_kids_with_the_greatest_number_of_candies.py
1768	Merge Strings Alternately	Easy	1768_merge_strings_alternately.py
345	Reverse Vowels of a String	Easy	345_reverse_vowels_of_a_string.py
151	Reverse Words in a String	Medium	151_reverse_words_in_a_string.py
283	Move Zeroes	Easy	283_move_zeroes.py
392	Is Subsequence	Easy	392_is_subsequence.py
238	Product of Array Except Self	Medium	238_product_of_array_except_self.py
443	String Compression	Medium	443_string_compression.py
334	Increasing Triplet Subsequence	Medium	334_increasing_triplet_subsequence.py
1732	Find the Highest Altitude	Easy	1732_find_the_highest_altitude.py
724	Find Pivot Index	Easy	724_find_pivot_index.py
643	Maximum Average Subarray I	Easy	643_maximum_average_subarray_i.py
2215	Find the Difference of Two Arrays	Easy	2215_find_the_difference_of_two_arrays.py
1207	Unique Number of Occurrences	Easy	1207_unique_number_of_occurrences.py
1456	Maximum Number of Vowels in a Substring of Given Length	Medium	1456_maximum_number_of_vowels_in_a_substring_of_given_length.py
1493	Longest Subarray of 1's After Deleting One Element	Medium	1493_longest_subarray_of_1s_after_deleting_one_element.py
1679	Max Number of K-Sum Pairs	Medium	1679_max_number_of_k_sum_pairs.py
1004	Max Consecutive Ones III	Medium	1004_max_consecutive_ones_iii.py
2390	Removing Stars From a String	Medium	2390_removing_stars_from_a_string.py
735	Asteroid Collision	Medium	735_asteroid_collision.py
2352	Equal Row and Column Pairs	Medium	2352_equal_row_and_column_pairs.py
11	Container With Most Water	Medium	11_container_with_most_water.py
1657	Determine if Two Strings Are Close	Medium	1657_determine_if_two_strings_are_close.py
394	Decode String	Medium	394_decode_string.py
933	Number of Recent Calls	Easy	933_number_of_recent_calls.py
649	Dota2 Senate	Medium	649_dota2_senate.py
206	Reverse Linked List	Easy	206_reverse_linked_list.py
328	Odd Even Linked List	Medium	328_odd_even_linked_list.py
2095	Delete the Middle Node of a Linked List	Medium	2095_delete_the_middle_node_of_a_linked_list.py
2130	Maximum Twin Sum of a Linked List	Medium	2130_maximum_twin_sum_of_a_linked_list.py

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Filename Convention

Pattern: {id}_{short_title_snake_case}.py

Examples:

• 1768_merge_strings_alternately.py
• 0001_two_sum.py

Rules:

• Start with the numeric problem id so files sort in problem order.
• Use snake_case for the short title; avoid spaces and special characters.

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File Header Template

Place this header at the top of every solution file so each file is self‑documenting.

# LeetCode {id} {Short Title}
# URL: https://leetcode.com/problems/{slug}/
# Difficulty: Easy|Medium|Hard
# Language: Python 3.10+

Concrete example:

# LeetCode 1768 Merge Strings Alternately
# URL: https://leetcode.com/problems/merge-strings-alternately/
# Difficulty: Easy
# Language: Python 3.10+

Include a small runnable example in each file using the if __name__ == "__main__": guard so running the file verifies behavior quickly.

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How to Run

Run a single solution:

python 1768_merge_strings_alternately.py

Quick test pattern inside files:

if __name__ == "__main__":
    print(Solution().mergeAlternately("abc", "xyz"))  # expected: axbycz