马走日

#include <stdio.h>
#include <string.h>

#define maxn 10


int arr[maxn + 5][maxn + 5];
//方向数组
int dir[8][2] = {
    {-2, 1}, {-2, -1}, {2, -1}, {2, 1}, 
    {-1, -2}, {-1, 2}, {1, -2}, {1, 2}
};
int n, m, sx, sy, t;
int ans = 0;

void dfs(int x, int y, int cnt){
    if(x < 0 || x >=n || y < 0 || y >= m) return;
    if(arr[x][y]) return;
    if(cnt == n * m){
        ans += 1;
        return;
    }
    arr[x][y] = 1;
    for (int k = 0; k < 8; k++) {
        int dx = x + dir[k][0];
        int dy = y + dir[k][1];
        dfs(dx, dy, cnt + 1);
       
    }
     arr[x][y] = 0;
}

int main() {
    
    scanf("%d", &t);
    while(t--) {
        memset(arr, 0, sizeof(arr));
        scanf("%d%d%d%d", &n, &m, &sx, &sy);
        int cnt = 1;
        dfs(sx, sy, cnt);
        printf("%d\n", ans);
        ans = 0;
    }
    

    return 0;
}