Cod sursa(job #2424158)

Utilizator alexburdescuBurdescu Alexandru alexburdescu Data 22 mai 2019 18:22:02
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.46 kb
#include <iostream>
#include <fstream>
using namespace std;
struct graf
{
    int c1,c2,dist;
}Noduri[500005];
int distanta[500005], tata[500005];
int N,M;
int cont=0;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
int main()
{
    fin>>N>>M;
    for(int i=1;i<=M;i++)                                   ///Citim Graful
    {
        fin>>Noduri[i].c1>>Noduri[i].c2>>Noduri[i].dist;
    }


    for(int i=1;i<=N;i++)     /// Initializam Graful
    {
        distanta[i]=999999999;     /// Declaram distantele initiale cu infinit
        tata[i]=0;
    }
    distanta[1]=0;             ///Distanta de la sursa e 0

    for(int i=1;i<=N;i++)    /// Relaxam muchiile
    {
        for(int j=1;j<=M;j++)
        {
            if(distanta[Noduri[j].c1]+Noduri[j].dist<distanta[Noduri[j].c2])
            {
                distanta[Noduri[j].c2]=distanta[Noduri[j].c1]+Noduri[j].dist;
                tata[Noduri[j].c2]=Noduri[j].c1;
            }
        }
    }

    for(int j=1;j<=M;j++)   /// Mai facem o verificare pentru toate muchiile pentru detectarea ciclurilor negative
    {
        if(distanta[Noduri[j].c1]+Noduri[j].dist<distanta[Noduri[j].c2] && cont==0)
        {
            cont++;
            fout<<"Ciclu negativ!";
        }
    }
    if(cont==0)                    ///Afisam Distantele
    {
        for(int i=2;i<=N;i++)
        {
            fout<<distanta[i]<<" ";
        }
    }
    return 0;
}