感觉跟题解差不多啊，不知道为什么就对一半 代码如下：

#include <iostream>
using namespace std;

int n, m, t, r=0;
int sx, sy, fx, fy, dx, dy;
int dir[4][2] = {
    {-1, 0}, {0, 1}, {1, 0}, {0, -1}
};

struct GRD {
    int is_barrier = 0;
    int x, y;
    int book = 0;
} grds[10][10];

void dfs(GRD &obj){
    if (obj.x == fx && obj.y == fy){
        ++r;
        return;
    }
    for (int i=0; i<4; ++i){
        dx = obj.x + dir[i][0];
        dy = obj.y + dir[i][1];
        if (dx<1 || dx>n || dy<1 || dy>m || grds[dx][dy].is_barrier || grds[dx][dy].book) continue;
        grds[dx][dy].book = 1;
        dfs(grds[dx][dy]);
        grds[dx][dy].book = 0;
    }
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> m >> t;
    cin >> sx >> sy >> fx >> fy;

    int bx, by;
    for (int i=0; i<t; ++i){
        cin >> bx >> by;
        grds[bx][by].is_barrier = 1;
    }
    for (int i=1; i<=n; ++i){
        for (int j=1; j<=m; ++j) {
            grds[i][j].x = i, grds[i][j].y = j;
        }
    }
    grds[sx][sy].book = 1;
    dfs(grds[sx][sy]);

    if (grds[fx][fy].is_barrier) cout << 0; 
    else cout << r;
    return 0;
}