Cod sursa(job #2359729)

Utilizator Tudor2PopescuPopescu Tudor-Cristian Tudor2Popescu Data 1 martie 2019 08:52:59
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.55 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define INF 0x3f3f3f3f;
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
int n,m;
vector <pair<int, int>>graf[5005];
vector <int> v;
queue <int> coada;
int d[5005];
int viz[5005];
int esteincoada[5005];
bool bellmanford(int s)
{
    for(int i=1;i<=n;i++)
    {
        viz[i]=0;
        esteincoada[i]=0;
        d[i]=INF;
    }
    d[s]=0;
    coada.push(s);
    esteincoada[s]=1;
    while(!coada.empty())
    {
        int nodcurent=coada.front();
        viz[nodcurent]++;
        if(viz[nodcurent]>=n)
        {
            return false;
        }
        coada.pop();
        esteincoada[nodcurent]=0;
        for(size_t i=0;i<graf[nodcurent].size();i++)
        {
            int vecin=graf[nodcurent][i].first;
            int cost=graf[nodcurent][i].second;
            if(d[nodcurent]+cost<d[vecin])
            {
                d[vecin]=d[nodcurent]+cost;
                if(!esteincoada[vecin])
                {
                    coada.push(vecin);
                }
            }

        }
    }
    return true;
}
int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y,c;
        fin>>x>>y>>c;
        graf[x].push_back(make_pair(y,c));
    }
    if(bellmanford(1))
    {
        for(int i=2;i<=n;i++)
        {
            fout<<d[i]<<" ";
        }
    }
    else
    {
        fout<<"Ciclu negativ!";
    }
    fin.close();
    fout.close();
    return 0;
}