#!/usr/bin/env python
# 2025 - Advent Of Code 4 part 2

# file = 'input_example.txt'
file = 'input.txt'

# pylint: disable=consider-using-with
input_lines = [list(line.strip('\n')) for line in open(file, encoding="utf-8")]
MAX_X = len(input_lines[0])
MAX_Y = len(input_lines)

for pos_y in range(0, MAX_Y):
    for pos_x in range(0, MAX_X):
        print(input_lines[pos_y][pos_x], end='')
    print()
print()

total_removed = 0
accessible = 1
while accessible != 0:
    new_grid = [[input_lines[y][x] for x in range(MAX_X)] for y in range(MAX_Y)]
    accessible = 0
    for pos_y in range(0, MAX_Y):
        for pos_x in range(0, MAX_X):
            if input_lines[pos_y][pos_x] == '@':
                rolls = 0
                if pos_y > 0 and pos_x > 0 and input_lines[pos_y-1][pos_x-1] == '@':
                    rolls += 1
                if pos_y > 0 and input_lines[pos_y-1][pos_x] == '@':
                    rolls += 1
                if pos_y > 0 and pos_x < MAX_X - 1 and input_lines[pos_y-1][pos_x+1] == '@':
                    rolls += 1
                if pos_x > 0 and input_lines[pos_y][pos_x-1] == '@':
                    rolls += 1
                if pos_x < MAX_X - 1 and input_lines[pos_y][pos_x+1] == '@':
                    rolls += 1
                if pos_y < MAX_Y - 1 and pos_x > 0 and input_lines[pos_y+1][pos_x-1] == '@':
                    rolls += 1
                if pos_y < MAX_Y - 1 and input_lines[pos_y+1][pos_x] == '@':
                    rolls += 1
                if pos_y < MAX_Y - 1 and pos_x < MAX_X - 1 and input_lines[pos_y+1][pos_x+1] == '@':
                    rolls += 1

                if rolls < 4:
                    accessible += 1
                    new_grid[pos_y][pos_x] = 'x'
                else:
                    new_grid[pos_y][pos_x] = input_lines[pos_y][pos_x]

    # for pos_y in range(0, MAX_Y):
    #     for pos_x in range(0, MAX_X):
    #         print(input_lines[pos_y][pos_x], end='')
    #     print()
    input_lines = new_grid.copy()
    total_removed += accessible

print(total_removed)