#include<bits/stdc++.h>
using namespace std;
int fa[1000005];
int find(int x){
	return fa[x]==x?x:fa[x]=find(fa[x]);
} 
void Union(int x,int y){
	x=find(x);
	y=find(y);
	if(x!=y){
		fa[x]=y;
	}
}
int main(){
    map<int,int> mp;
	vector<pair<int,int> > vec;
    int t;
    cin>>t;
    while(t--){
    	mp.clear();
    	vec.clear();
    	int n;
    	cin>>n;
    	for(int i=1;i<=n;i++){
    		fa[i]=i;
		}
    	int cnt=0;
    	for(int i=1;i<=n;i++){
    		int e,x,y;
    		cin>>x>>y>>e;
			if(mp.find(x)==mp.end()){
    			cnt++; 
    			mp[x]=cnt;
			}
			if(mp.find(y)==mp.end()){
    			cnt++; 
    			mp[y]=cnt;
			}
    		if(e==1){
    			Union(mp[x],mp[y]);
			}
			if(e==0){
				 vec.push_back({mp[x],mp[y]});
			}
		}
		for(int i=0;i<vec.size();i++){
			if(find(vec[i].first)==find(vec[i].second)){
				cout<<"NO"<<endl;
				goto nmsl;
			}
		}
		cout<<"YES"<<endl;
		nmsl:;
	}
	return 0;
}

3,8点WA，2点TLE，求助