POJ 3259 Wormholes

#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<string>
#include<string.h>
#include<math.h>
#include<limits.h>
#include<time.h>
#include<stdlib.h>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<vector>
#define LL long long

using namespace std;

struct node
{
    int u, v, value;
    node(int u, int v, int value) : u(u), v(v), value(value) {}
    node() {}
} edge[5300];
int n, m, w, cnt;
int dis[505];
const int inf = 0x3f3f3f3f;
bool BellmanFord()
{
    memset(dis, inf, sizeof dis);
    dis[1] = 0;
    for(int i = 0; i < n - 1; i++)
        for(int j = 0; j < cnt; j++)
            dis[edge[j].v] = min(dis[edge[j].u] + edge[j].value, dis[edge[j].v]);
    for(int i = 0; i < cnt; i++)
    {
        if(dis[edge[i].v] > dis[edge[i].u] + edge[i].value)
            return 1;
    }
    return 0;
}
int main()
{
    int T;
    while(~scanf("%d", &T))
    {
        while(T--)
        {
            cnt = 0;
            scanf("%d%d%d", &n, &m, &w);
            for(int i = 0; i < m; i++)
            {
                int u, v, value;
                scanf("%d%d%d", &u, &v, &value);
                edge[cnt++] = node(u, v, value);
                edge[cnt++] = node(v, u, value);
            }
            for(int i = 0; i < w; i++)
            {
                int u, v, value;
                scanf("%d%d%d", &u, &v, &value);
                edge[cnt++] = node(u, v, -value);
            }
            if(BellmanFord())
                puts("YES");
            else
                puts("NO");
        }
    }
    return 0;
}