Submission #1318750

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Source Code Expand

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

const int DIM = 2e5 + 5;

int oki[DIM];
vector<int> edg[DIM];

void dfs( int x ) {
    oki[x] = 1;
    
    for( int y : edg[x] ) {
        if( oki[y] == 0 )
            dfs( y );
    }
    
    return;
}

int main( void ) {
    
    int n, m;
    cin >> n >> m;
    
    for( int i = 1; i <= n; i ++ ) {
        int s;
        cin >> s;
        
        for( int j = 1; j <= s; j ++ ) {
            int x;
            cin >> x;
            
            edg[i].push_back( x + n );
            edg[x + n].push_back( i );
        }
    }
    
    dfs( 1 );
    if( accumulate( oki + 1, oki + n + 1, 0 ) == n )
        cout << "YES\n";
    else
        cout << "NO\n";
    
    return 0;
}

Submission Info

Judge Result