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为了解决这个问题，我们需要在给定的网格地图上部署尽可能多的炮兵部队，同时确保任何两支炮兵部队之间不能互相攻击。攻击范围是每个炮兵部队横向和纵向各两格，包括其所在的位置。

方法思路

解决代码

import sysfrom sys import stdindef main():    n, m = map(int, stdin.readline().split())    grid = []    for _ in range(n):        line = stdin.readline().strip()        grid.append(line)        # 预处理attak_matrix    attak_matrix = [[False for _ in range(m)] for _ in range(m)]    for x in range(m):        for y in range(m):            if (x == y + 1 and x != y) or (y == x + 1 and y != x):                attak_matrix[x][y] = True            elif (x == y - 1 and x != y) or (y == x - 1 and y != x):                attak_matrix[x][y] = True        # 预处理allowed_masks    allowed_masks = [set() for _ in range(1 << m)]    for current_mask in range(1 << m):        current_attack = 0        for x in range(m):            if (current_mask >> x) & 1:                current_attack |= (1 << x)        for prev_mask in range(1 << m):            prev_attack = 0            for y in range(m):                if (prev_mask >> y) & 1:                    prev_attack |= (1 << y)            conflict = False            for x in range(m):                if (current_mask >> x) & 1:                    for y in range(m):                        if (prev_mask >> y) & 1 and attak_matrix[x][y]:                            conflict = True                            break                    if conflict:                        break            if not conflict:                allowed_masks[current_mask].add(prev_mask)        # 初始化动态规划    dp = [ [-1 for _ in range(1 << m)] for _ in range(n+1)]    dp[0][0] = 0        for i in range(1, n+1):        for current_mask in range(1 << m):            # 检查当前mask是否有炮兵在H的位置            valid = True            for x in range(m):                if (current_mask >> x) & 1 and grid[i-1][x] == 'H':                    valid = False                    break            if not valid:                continue            current_count = bin(current_mask).count('1')            max_prev = 0            for prev_mask in allowed_masks[current_mask]:                if dp[i-1][prev_mask] != -1:                    if dp[i-1][prev_mask] + current_count > max_prev:                        max_prev = dp[i-1][prev_mask] + current_count            if max_prev > 0:                dp[i][current_mask] = max_prev            else:                dp[i][current_mask] = current_count if current_count > 0 else 0        max_result = 0    for mask in range(1 << m):        if dp[n][mask] > max_result:            max_result = dp[n][mask]    print(max_result)if __name__ == "__main__":    main()

代码解释

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