这是题目，不知哪错了

#include <bits/stdc++.h>
using namespace std;
int Map[45][45];
int n, m, qx, qy, zx, zy;
int head, tail = 1;
int x[45], y[45], pre[45];
int fxx[5] = {0, 0, 1, 0, -1};
int fxy[5] = {0, 1, 0, -1, 0};
void bfs() {
	int find;
	while (head < tail) {
		head++;
		for (int i = 1; i <= 4; i++) {
			int dx = x[head] + fxx[i];
			int dy = y[head] + fxy[i];
			bool k = (dx >= 1 && dx <= n) && (dy >= 1 && dy <= m);
			if (Map[dx][dy] == 0 && k) {
				tail++;
				x[tail] = dx;
				y[tail] = dy;
				pre[tail] = pre[head] + 1;
				Map[dx][dy] = 1;
				if (dx == zx && dy == zy) {
					cout << "jl/n";
					find = 1;
					cout << pre[tail];

					break;
				}
			}
		}
		if (find) {
			break;
		}
	}
	if (find == 0) {
		cout << -1;
	}
}

int main() {
	for (int i = 0; i <= 44; i++) {
		for (int j = 0; j <= 44; j++) {

			Map[i][j] = 1;
		}
	}
	char t;
//	while (1) {
	cin >> n >> m;
//		if (n == 0 && m == 0) {
//			break;
//		}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			cin >> t;
			if (t == '@') {
				qx = i;
				qy = j;
			}
			if (t == '*') {
				zx = i;
				zy = j;
			}
			Map[i][j] = (t == '#' ?  1 : 0);
		}
	}
	x[1] = qx;
	y[1] = qy;
	pre[1] = 0;
	bfs();
//	}
	return 0;
}```