Submission #992393

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Source Code Expand

#include<bits/stdc++.h>
using namespace std;


typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<vvd> vvvd;
typedef pair<int, int> pii;
typedef vector<pii> vpii;

#define pb push_back
#define mp make_pair
#define snd second
#define fst first
#define debug printf("--%d--\n",__LINE__)
#define ll long long int

int N, M;
int main(void){
	cin >> N >> M;
	vvi l(N);
	vvi mem(M);
	for(int i=0;i<M;i++){
		vi a;
		mem[i] = a;
	}
	int K[N];
	for(int i=0;i<N;i++){
		cin >> K[i];
		vector<int> a;
		for(int j=0;j<K[i];j++){
			int tmp;
			cin >> tmp;
			a.pb(tmp-1);
			mem[tmp-1].pb(i);
		}
		l.pb(a);
	}
	
	//set<pair<int,int> > s;
	vvi e(N);
	for(int i=0;i<N;i++){vi a; e[i]=a;}
	for(int i=0;i<M;i++){
		for(int j=1;j<mem[i].size();j++){
			//s.insert(mp(mem[i][0], mem[i][j]));
			//s.insert(mp(mem[i][j], mem[i][0]));
			e[mem[i][0]].pb(mem[i][j]);
			e[mem[i][j]].pb(mem[i][0]);
			//cout << mem[i][0] << " " << mem[i][j] << endl;
		}
	}
	
	
	int flg[N] = {0};int cnt = 1;
	queue<int> q;
	q.push(0);flg[0] = 1;
	while(!q.empty()){
		int now = q.front(); q.pop();
		for(int i=0;i<e[now].size();i++){
			if (flg[e[now][i]]==0){
				flg[e[now][i]] = 1;cnt++;
				q.push(e[now][i]);
			}
		}
	}
	if (cnt==N) cout << "YES" << endl; else cout << "NO" << endl;
	
	
	
	return 0;
}

Submission Info

Judge Result