警钟短鸣：奇异搞笑DFS无法通过！

#include<bits/stdc++.h>
using namespace std;
int List[20][20] , cnt = 0;
int n;
queue<pair<int , int> > q;
void dfs(int x , int y , int cntt , queue<pair<int , int> > Path){ 
    if(x == n and y == n){
        if(cnt < cntt){
            cnt = cntt;
            while(!Path.empty()){
                q.push(Path.front());
                Path.pop();
            }
        }
        return;
    }
    if(x + 1 <= n){
        Path.push(make_pair(x + 1 , y));
        dfs(x + 1 , y , cntt + List[x][y] , Path);
    }
    if(y + 1 <= n){
        Path.push(make_pair(x , y + 1));
        dfs(x , y + 1 , cntt + List[x][y] , Path);
    }
}
int main(){
    cin >> n;
    while(true){
        int a , b , c;
        cin >> a >> b >> c;
        if(a == 0 and b == 0 and c == 0){
            break;
        }
        List[a][b] = c;
    }
    int res = 0;
    dfs(1 , 1 , 0 , q);
    res += cnt;
    while(!q.empty()){
        int a = q.front().first , b = q.front().second;
        List[a][b] = 0;
        q.pop();
    }
    cnt = 0; 
    dfs(1 , 1 , 0 , q);
    cout << res + cnt << endl;
}