def main():
    grid = [ [ int(c) for c in line.strip() ] for line in open('inputs/10.txt') ]

    WIDTH = len(grid[0])
    HEIGHT = len(grid)

    total = 0

    # print(WIDTH, HEIGHT)

    for y, line in enumerate(grid):
        for x, c in enumerate(line):
            if c == 0:
                s = set()
                s.add(( x, y ))
                total += search(0, s, grid)
    
    print(f"Day 10 part 1: {total}")

def search(level, items, grid) -> int:
    if level == 9:
        return len(items)

    s = set()
    new_level = level + 1
    
    for x, y in items:
        if x - 1 >= 0 and grid[y][x - 1] == new_level:
            s.add(( x-1, y ))
        if x + 1 < len(grid[0]) and grid[y][x + 1] == new_level:
            s.add(( x+1, y ))
        if y - 1 >= 0 and grid[y-1][x] == new_level:
            s.add(( x, y-1 ))
        if y + 1 < len(grid) and grid[y+1][x] == new_level:
            s.add(( x, y+1 ))

    return search(new_level, s, grid)


# if __name__ == '__main__':
main()