Day 21 part 1

g = open("input").read().splitlines()
q = [(i, j) for i in range(len(g)) for j in range(len(g[0])) if g[i][j] == 'S']
dirs = [(0, 1), (-1, 0), (0, -1), (1, 0)]
for _ in range(64):
    next_q = []
    v = set()
    while q:
        x, y = q.pop()
        for d in dirs:
            x, y = x + d[0], y + d[1]
            if 0 <= x < len(g) and 0 <= y < len(g[0]) and g[x][y] != '#' and (x, y) not in v:
                v.add((x, y))
                next_q.append((x, y))
    q = next_q

print(f'Part1: {len(v)}')