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为了解决农农在浙农林大学行走时不踩进水坑的问题，我们需要设计一个程序来判断他能否在给定的水位下安全地从起点 (1, 1) 到达终点 (n, n)。我们可以使用二分查找配合广度优先搜索（BFS）来高效解决这个问题。

方法思路

解决代码

import sysfrom collections import dequedef main():    data = list(map(int, sys.stdin.read().split()))    ptr = 0    n = data[ptr]    ptr += 1    a = []    for i in range(n):        row = data[ptr:ptr + n]        ptr += n        a.append(row)        def check(mid):        visited = [[0] * (n + 1) for _ in range(n + 1)]        q = deque()        q.append((1, 1))        visited[1][1] = 1        if a[1][1] > mid or a[n][n] > mid:            return False        if n == 1:            return True        directions = [(-1, 0), (1, 0), (0, -1), (0, 1)]        while q:            x, y = q.popleft()            for dx, dy in directions:                nx = x + dx                ny = y + dy                if 1 <= nx <= n and 1 <= ny <= n:                    if not visited[nx][ny] and a[nx][ny] <= mid:                        if nx == n and ny == n:                            return True                        visited[nx][ny] = 1                        q.append((nx, ny))        return False    low = 1    high = 100000    max_X = 0    while low <= high:        mid = (low + high) // 2        can = check(mid)        if can:            max_X = mid            low = mid + 1        else:            high = mid - 1    q_num = data[ptr]    ptr += 1    for _ in range(q_num):        x = data[ptr]        ptr += 1        if x <= max_X:            print("Wuhu")        else:            print("Hmmm")if __name__ == "__main__":    main()

代码解释

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