P1605 迷宫 求助（玄关）

#include <bits/stdc++.h>
using namespace std;
int m[6][6], cnt = 0;
int sx, sy, ex, ey;
bool mark[6][6];



int dx[4] = {0, 0, 1, -1}, dy[4] = {-1, 1, 0, 0};

void dfs(int x, int y) {
	if (x == ex && y == ey) {
		cnt++;
		return ;
	} else {
		for (int i = 0; i <= 3; i++) {
			if ((m[x + dx[i]][y + dy[i]] == 1) && (mark[x + dx[i]][y + dy[i]] == 0)) {
				mark[x + dx[i]][y + dy[i]] = 1;
				dfs(x + dx[i], y + dy[i]);
				mark[x + dx[i]][y + dy[i]] = 0;
			}
		}
	}
}

int main() {
	int n, m, t, x, y;
	cin >> n >> m >> t;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			m[i][j] = 1;
		}
	}
	cin >> sx >> sy;
	cin >> ex >> ey;
	while (t--) {
		cin >> x >> y;
		m[x][y] = 0;
	}
	dfs(sx, sy);
	cout << cnt << endl;
	return 0;
}