Cod sursa(job #2195321)

Utilizator MikeStrikeAgache Mihai MikeStrike Data 15 aprilie 2018 23:59:08
Problema Algoritmul Bellman-Ford Scor 15
Compilator cpp Status done
Runda Arhiva educationala Marime 1.32 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define INF 0x3f3f3f3f
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
int n,m;
vector< pair<int, int> >graf[5005];
queue <int> coada;
int d[5005];
int viz[5005];
int esteincoada[5005];
bool bellmanford(int nodS)
{
    for(int i=1;i<=n;i++)
    {
        viz[i]=0;
        esteincoada[i]=0;
        d[i]=INF;
    }
    d[nodS]=0;
    coada.push(nodS);
    esteincoada[nodS]=1;
    while(!coada.empty())
    {
        int nod=coada.front();
        viz[nod]++;
        if(viz[nod]>=n) return false;
        coada.pop();
         esteincoada[nod] = 0;
         for(size_t i=0;i<graf[nod].size();i++)
         {
              int vecin=graf[nod][i].first;
            int cost=graf[nod][i].second;
            if(d[nod]+cost<d[vecin])
            {
                d[vecin]=d[nod]+cost;
                if(!esteincoada[vecin])
                    coada.push(vecin);
            }
         }
    }
    return true;
}
int main()
{in>>n>>m;
for(int i=1;i<=m;i++)
{
    int x,y,c;
    in>>x>>y>>c;
    graf[x].push_back(make_pair(y,c));
}
  if(bellmanford(1))
    {
        for(int i=2;i<=n;i++)
            out<<d[i]<<" ";
    }
    else
      out<<"Ciclu negativ";
    return 0;
}