DFS——迷宫

迷宫

        dfs简单路径搜索

#include
using namespace std;
#define rep(i,a,n) for(int i = a;i
#define per(i,a,n) for(int i = n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
#define yes cout<<"YES"<<'\n';
#define no cout<<"NO"<<'\n';
#define endl '\n';
#define R register
typedef vector<int> VI;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll MOD=1000000007;
int rnd(int x) {return mrand() % x;}
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;};
ll lcm(int a,int b){return a*b/gcd(a,b);};
 
int dx[4]={0,0,-1,1};
int dy[4]={-1,1,0,0};
int n;
string g[110];
int vis[110][110];
 
int a,b,c,d;
 
bool dfs(int x,int y){
	if(x<0||x>=n||y<0||y>=n||vis[x][y]||g[x][y]=='#') return 0;
	vis[x][y]=1;
	if(x==c&&y==d) return 1;
	rep(i,0,4){
		if(dfs(x+dx[i],y+dy[i])) return 1;
	}
	return 0;
}
 
int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	int T;
	cin>>T;
	while(T--){
		cin>>n;
		rep(i,0,n) cin>>g[i];
		memset(vis,0,sizeof vis);
		cin>>a>>b>>c>>d;
		if(dfs(a,b)) puts("YES");
		else puts("NO");
	}
	return 0;
}