adventofcode/2021/python/day-03/main.py at master · Mishco/adventofcode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
from collections import Counter


def part1(test_input: str) -> int:
    ll = test_input.strip().splitlines()

    gamma_rate = ""
    epsilon_rate = ""
    for i in range(len(ll[0])):
        x = ""
        for j in ll:
            x += j[i]

        gamma_rate += Counter(x).most_common()[0][0]
        epsilon_rate += Counter(x).most_common()[1][0]

    result = int(gamma_rate, 2) * int(epsilon_rate, 2)
    return result


def part2(test_input: str) -> int:
    ll = test_input.strip().splitlines()
    theta = ""
    epsilon = ""
    for i in range(len(ll[0])):
        common = Counter([x[i] for x in ll])

        if common["0"] > common["1"]:
            ll = [x for x in ll if x[i] == "0"]
        else:
            ll = [x for x in ll if x[i] == "1"]
        theta = ll[0]

    ll = test_input.strip().splitlines()
    for i in range(len(ll[0])):
        common = Counter([x[i] for x in ll])

        if common["0"] > common["1"]:
            ll = [x for x in ll if x[i] == "1"]
        else:
            ll = [x for x in ll if x[i] == "0"]
        if ll:
            epsilon = ll[0]
    return int(theta, 2) * int(epsilon, 2)


if __name__ == "__main__":
    test_in = """00100
11110
10110
10111
10101
01111
00111
11100
10000
11001
00010
01010"""

    assert part1(test_in) == 198

    f = open("../inputs/2021-03.txt", mode="r").read()
    res = part1(f)
    print(res)

    assert part2(test_in) == 230
    res = part2(f)
    print(res)