/*
ID: Keqi Zhao
TASK: test
LANG: C++                 
*/
#include <iostream>
#include <cstdio>
#include <algorithm>
#define Maxn 1000010
using namespace std;
int n, bt, ct, T, b[Maxn * 2], c[Maxn * 2], fa[Maxn * 2];
struct node{
	int x, y, z;
}a[Maxn];
int find (int x){
	if(fa[x] == x)
		return x;
	return fa[x] = find(fa[x]);
}
void merge(int x, int y){
	x = find(x);
	y = find(y);
	if(x != y)
		fa[x] = y;
}
int main() {
	cin >> T;
	while(T--){
		cin >> n;
		bt = 0, ct = 0;
		for(int i = 1; i <= n; i ++){
			cin >> a[i].x >> a[i].y >> a[i].z;
			b[++bt] = a[i].x;
			b[++bt] = a[i].y;
		}
		sort(b + 1, b  + bt + 1);
		for(int i = 1; i <= bt; i++)
			if(b[i] != b[i - 1])
				c[++ct] = b[i];
		for(int i = 1; i <= bt; i++){
			a[i].x = lower_bound(c + 1, c + ct + 1, a[i].x) - c;
			a[i].y = lower_bound(c + 1, c + ct + 1, a[i].y) - c;
		}
		for(int i = 1; i <= ct; i++)
			fa[i] = i;
		for(int i = 1; i <= n; i++)
			if(a[i].z)
				merge(a[i].x , a[i].y);
		bool flag = true;
		for(int i = 1; i <= n; i++)
			if(!a[i].z)
				if(find(a[i].x) == find(a[i].y)){
					flag = false;
					break;
				}
		cout << (flag  ? "YES" : "NO") << endl;
	}
	return 0;
}