text: str

with open("input.txt") as f:
    text = f.read()

total: int  = 0

def eval(lines: list[str], x: int, y: int):
    start_x = max(x - 1, 0)
    stop_x = min(len(lines[0]), x + 2)
    start_y = max(y - 1, 0)
    stop_y = min(len(lines[0]), y + 2)
    
    count: int = 0

    for line in lines[start_y:stop_y]:
        count += line[start_x:stop_x].count("@")
    
    return ((count - 1) < 4)
    

lines = [[c for c in line] for line in text.splitlines()]

bozo = 1
while bozo:
    bozo = 0
    for y, line in enumerate(lines):
        for x, c in enumerate(line):
            if c == "@":
                if (eval(lines, x, y)):
                    total += 1
                    line[x] = "x"
                    bozo = 1

print(total)