Rt,代码如下：

// Problem : 【数据删除】
// Contest : UOJ - 【数据删除】
// URL : http://【数据删除】/contest/292/problem/337
// Memory Limit : 1024 MB
// Time Limit : 1000 ms
// Powered by CP Editor (https://github.com/cpeditor/cpeditor)

#include <algorithm>
#include <iostream>
#include <map>
#pragma GCC operize( 2 )
using namespace std;
int fa[ 200010 ];
void init( int n )
{
    for ( int i = 0; i <= n; i++ )
        fa[ i ] = i;
}
int find( int x )
{
    if ( fa[ x ] == x )
        return x;
    return fa[ x ] = find( fa[ x ] );
}
bool query( int x, int y )
{
    return ( find( x ) == find( y ) );
}
void merge( int x, int y )
{
    x = find( x );
    y = find( y );
    fa[ x ] = y;
}
int lsh( int x, int ls[], int n )
{
    return lower_bound( ls, ls + n, x ) - ls;
}
int main()
{
    int t;
    cin >> t;
    while ( t-- )
    {
        int n;
        cin >> n;
        bool flag = true;
        int x[ 100010 ], y[ 100010 ], opt[ 100010 ];
        int ls[ 200020 ];
        int cnt = 0;
        bool pfq0 = 1, pfq1 = 1;
        for ( int i = 0; i < n; i++ )
        {
            cin >> x[ i ] >> y[ i ] >> opt[ i ];
            ls[ cnt++ ] = x[ i ];
            ls[ cnt++ ] = y[ i ];
        }
        sort( ls, ls + cnt );
        int len = ls + cnt - unique( ls, ls + cnt );
        init( len + 10 );

        for ( int i = 0; i < n; i++ )
        {
            if ( opt[ i ] )
                merge( lsh( x[ i ], ls, len ), lsh( y[ i ], ls, len ) );
        }
        for ( int i = 0; i < n; i++ )
        {
            if ( !opt[ i ] )
            {
                if ( query( lsh( x[ i ], ls, len ), lsh( y[ i ], ls, len ) ) )
                {
                    flag = false;
                    break;
                }
            }
        }
        if ( flag )
        {
            cout << "YES" << endl;
        }
        else
        {
            cout << "NO" << endl;
        }
    }
}