uva: 558 - Wormholes

#include<stdio.h>
const int INF = 10000000;
const int MX = 2050;
int m,n,d[MX];

struct Node
{
    int u,v,w;
}nodes[MX];

void initializeSingleSource(int s)
{
    for(int i=0;i<n;i++)
    {
        d[i]=INF;
        d[s]=0;
    }
}

void relax(int u,int v ,int w)
{
    if(d[v]>d[u]+w)
    {
        d[v]=d[u]+w;
    }
}

bool bellmanFord(int s)
{
    initializeSingleSource(s);
    int i,j,k;
    for(i=0;i<n-1;i++)
    {
        for(j=0;j<m;j++)
        {
            relax(nodes[j].u,nodes[j].v,nodes[j].w);
        }
    }
    for(j=0;j<m;j++)
    {
        if (d[nodes[j].v] > d[nodes[j].u] + nodes[j].w)
            return false;
    }
    return true;
}

int main()
{
    int test;
    scanf("%d",&test);
    while(test--)
    {
        scanf("%d %d",&n,&m);
        int i,j,k,l;
        for(i=0;i<m;i++)
        {
            scanf("%d %d %d",&nodes[i].u,&nodes[i].v,&nodes[i].w);
        }
        if(!bellmanFord(0))printf("possible\n");
        else printf("not possible\n");
    }
    return 0;
}