学步园

题意 ：该死的FJ发现了时光倒流虫洞，问能不能看见过去的自己........

其实就是判断有没有负权回路，over了

code：

#include <set>
#include <map>
#include <ctime>
#include <queue>
#include <cmath>
#include <stack>
#include <limits>
#include <vector>
#include <bitset>
#include <string>
#include <cstdio>
#include <cstring>
#include <fstream>
#include <string.h>
#include <iostream>
#include <algorithm>
#define Si set<int>
#define LL long long
#define pb push_back
#define PS printf(" ")
#define Vi vector<int>
#define LN printf("\n")
#define lson l,m,rt << 1
#define rson m+1,r,rt<<1|1
#define SD(a) scanf("%d",&a)
#define PD(a) printf("%d",a)
#define SET(a,b) memset(a,b,sizeof(a))
#define FF(i,a) for(int i(0);i<(a);i++)
#define FD(i,a) for(int i(a);i>=(1);i--)
#define FOR(i,a,b) for(int i(a);i<=(b);i++)
#define FOD(i,a,b) for(int i(a);i>=(b);i--)
#define readf freopen("input.txt","r",stdin)
#define writef freopen("output.txt","w",stdout)
const int maxn = 501;
const int INF = 0x3fffffff;
const int dx[]={0,1,0,-1};
const int dy[]={1,0,-1,0};
const double pi = acos(-1.0);
using namespace std;
int N,M,W; //N farms, M paths, W Wormholes
int e_cnt, adj[maxn], cnt[maxn], dis[maxn];
bool vis[maxn];
queue<int> q;
struct Egde{
    int end;
    int next;
    int T;
}Graph[maxn<<3];
void add_p(int start, int end ,int T){
    Graph[e_cnt].end=end;
    Graph[e_cnt].T=T;
    Graph[e_cnt].next=adj[start];
    adj[start]=e_cnt++;

    Graph[e_cnt].end=start;
    Graph[e_cnt].T=T;
    Graph[e_cnt].next=adj[end];
    adj[end]=e_cnt++;
}
void add_w(int start, int end ,int T){
    Graph[e_cnt].end=end;
    Graph[e_cnt].T=-T;
    Graph[e_cnt].next=adj[start];
    adj[start]=e_cnt++;
}
// 因为我们aim 是判断一下负权回路，所以并不需要每个点都spfa
bool spfa(){
    while(!q.empty()) q.pop();
    SET(vis,false);
    SET(cnt,0);
    FOR(i,1,N) dis[i]=INF;
    vis[1]=true;
    dis[1]=0;
    cnt[1]=1;
    q.push(1);

    while(!q.empty()){

        int tmp=q.front();
        q.pop();
        vis[tmp]=false;
        for(int i=adj[tmp];i;i=Graph[i].next){
            int t=Graph[i].T;
            int end=Graph[i].end;

            if(dis[end] > dis[tmp]+t){
                dis[end]=dis[tmp]+t;

                if(!vis[end]){
                    vis[end]=true;
                    if(++cnt[end]>N)
                        return true;
                    q.push(end);
                }
            }
        }

    }
    //PD(dis[3]);LN; 我晕 忘了注释这句 ，wa了一次
    return false;

}
void print(int u){
    for(int i=adj[u];i;i=Graph[i].next)
        printf("%d--------->%d  edge:  %d\n",u,Graph[i].end,Graph[i].T);
}
int main(){
    int cas;
    SD(cas);
    while(cas--){
        SET(adj,0);
        e_cnt=1;
        scanf("%d%d%d",&N,&M,&W);
        int A,B,T;
        FF(i,M){
            scanf("%d%d%d",&A,&B,&T);
            add_p(A,B,T);
        }
        FF(i,W){
            scanf("%d%d%d",&A,&B,&T);
            add_w(A,B,T);
        }
//        FOR(i,1,N){
//            print(i);
//        }
        if(spfa()) puts("YES");
        else puts("NO");
    }
	return 0;
}