#include<stdio.h>#include<string.h>#include<limits.h>#include<queue>using namespace std;#define N 5505#define M 55000//注意边和点集的数组大小struct edge{    int to,value,next;}edges[M];int heads[N],len=0;int addedge(int u,int v,int w){    edges[len].to=v,edges[len].value=http://www.mamicode.com/w,edges[len].next=heads[u];    heads[u]=len++;    return 0;}int n,m;int spfa(int v){    queue<int> q;    int inqueue[N],dis[N];    memset(inqueue,0,sizeof(inqueue)),inqueue[v]=1;    q.push(v);    for(int i=0;i<n;i++) dis[i]=INT_MAX;    dis[v]=0;    int times[N];    memset(times,0,sizeof(times)),times[v]=1;    while(!q.empty()){        int x=q.front();        q.pop();        inqueue[x]=0;        for(int j=heads[x];j!=-1;j=edges[j].next){            int to=edges[j].to,value=http://www.mamicode.com/edges[j].value;            if(value+dis[x]<dis[to]){                dis[to]=value+dis[x];                if(!inqueue[to]){  //注意已经在队列里面的不用再加入队列                    if(++times[to]>=n) return 0;                    inqueue[to]=1,q.push(to);                }            }        }    }    return 1;}int main(void){    int i,j,t;    int a,b,c;    scanf("%d",&t);    while(t--){        int w;        memset(heads,-1,sizeof(heads));//注意不要忘记        scanf("%d%d%d",&n,&m,&w);        while(m--){            scanf("%d%d%d",&a,&b,&c);            addedge(a-1,b-1,c);            addedge(b-1,a-1,c);                }        while(w--){            scanf("%d%d%d",&a,&b,&c);            addedge(a-1,b-1,-c);        }        if(!spfa(0)) printf("YES\n");        else printf("NO\n");    }    }