Submission #1678307

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Source Code Expand

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

vector<bool> used;
vector<vector<int> > l;

void search(int idx){
  for(int i=0; i<(int)l.size(); i++){
    if(used[i]) continue;
    int a=0, b=0;
    while(a<(int)l[idx].size() && b<(int)l[i].size()){
      if(l[idx][a]==l[i][b]){
        used[i] = true;
        search(i);
        break;
      }else if(l[idx][a] < l[i][b]){
        a++;
      }else{
        b++;
      }
    }                                
  }
}

int main(){
  int n,m;
  cin >> n >> m;

  vector<vector<int> > lang(n);
  for(int i=0; i<n; i++){
    int k;
    cin >> k;
    lang[i].resize(k);
    for(int j=0; j<k; j++){
      cin >> lang[i][j];
    }
    sort(lang[i].begin(), lang[i].end());
  }

  vector<bool> u(n, false);
  u[0] = true;
  used = u;
  l = lang;
  

  search(0);
  bool success = true;
  for(int i=0; i<n; i++){
    if(!used[i]){
      success = false;
    }
  }

  if(success){
    cout << "YES" << endl;
  }else{
    cout << "NO" << endl;
  }
  return 0;
}

Submission Info

Judge Result