Cod sursa(job #2176166)

Utilizator dragosmdvMoldovan Dragos dragosmdv Data 16 martie 2018 21:21:47
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.06 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");

vector<pair<int, int > > v[50005];

int n, a, m, aux, nr, b, c,freq[50005], cost[50005] ,inf=999999999;
queue <int> q;
pair <int, int>x;
int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>a>>b>>c;
        v[a].push_back(make_pair(b,c));
    }

    for(int i=2; i<=n; i++)
        cost[i]=inf;

    q.push(1);
    while(!q.empty())
    {

        int aux=q.front();
        if(freq[aux]>n)
        {
            fout<<"Ciclu negativ!";
            return 0;
        }
        q.pop();
        for(int i=0; i<v[aux].size(); i++)
        {
            x=v[aux][i];
            if(cost[x.first]>cost[aux]+x.second)
            {
                cost[x.first]=cost[aux]+x.second;
                q.push(x.first);
                freq[x.first]++;
            }

        }
    }

    for(int i=2; i<=n; i++)
        fout<<cost[i]<<" ";

    return 0;
}