Cod sursa(job #1610180)

Utilizator alex.craciunCraciun Alexandru alex.craciun Data 23 februarie 2016 12:29:16
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp Status done
Runda Arhiva educationala Marime 1.09 kb
#include <cstdio>
#include <vector>
#include <queue>
#include<climits>
#define inf INT_MAX/2
using namespace std;

vector <pair<int,int> > lv[50001];
vector <pair<int,int> >::iterator ii;
queue <int> q;
bool is_in_q[50001];
int d[50001];

int main()
{
    int n,m,i,x,y,c;
    FILE *f=fopen("bellmanford.in","r");
    fscanf(f,"%d%d",&n,&m);
    for(i=1;i<=m;i++)
    {
        fscanf(f,"%d%d%d",&x,&y,&c);
        lv[x].push_back(make_pair(y,c));
    }
    for(i=1;i<=n;i++)
        d[i]=inf;
    d[1]=0;is_in_q[1]=1;
    q.push(1);
    while(!q.empty())
    {
        x=q.front();q.pop();
        is_in_q[x]=0;
        for(ii=lv[x].begin();ii!=lv[x].end();ii++)
            if(d[x]+ ii->second < d[ii->first])
            {
                d[ii->first]=d[x]+ ii->second;
                if(!is_in_q[ii->first])
                {
                    q.push(ii->first);
                    is_in_q[ii->first]=1;
                }
            }
    }
    f=fopen("bellmanford.out","w");
    for(i=2;i<=n;i++)
        fprintf(f,"%d ",d[i]==inf?0:d[i]);
    return 0;
}