problem
solution
codes
#include<iostream>
#include<queue>
using namespace std;
struct xyz{
int x, y;
xyz(int x = 0, int y = 0):x(x),y(y){};
};
int m, n, book[20][20];
char a[20][20];
const int dx[] = {0,1,-1,0};
const int dy[] = {1,0,0,-1};
int main(){
cin>>m;
while(m--){
cin>>n;
for(int i = 0; i < n; i++)cin>>a[i];
bool ok = false;
queue<xyz>q; q.push(xyz(0,0));
while(!q.empty()){
xyz t = q.front(); q.pop();
book[t.x][t.y] = 1;
if(t.x==n-1 && t.y==n-1){ ok = true; break;}
for(int i = 0; i < 4; i++){
int newx = t.x+dx[i], newy = t.y+dy[i];
if(newx>=0 && newx<n && newy>=0 && newy<n && (a[newx][newy]=='.'||a[newx][newy]=='e') && !book[newx][newy])
{ book[newx][newy] = 1; q.push(xyz(newx, newy)); }
}
}
if(ok)cout<<"YES
";else cout<<"NO
";
}
return 0;
}