aoc day 3 a

day3_a.py

with open("input.txt", "r") as f:
    r = None
    for l in f.read().splitlines():
        if r is None:
            r = [[0, 0] for i in range(len(l))]

        for i, x in enumerate(l):
            r[i][x == "1"] += 1
    
    gamma, epsilon = 0, 0

    for i, (a, b) in enumerate(r[::-1]):
        if a > b:
            epsilon |= 1 << i
        else:
            gamma |= 1 << i

    print(gamma * epsilon)