Cod sursa(job #1987119)

Utilizator patcasrarespatcas rares danut patcasrares Data 29 mai 2017 20:10:45
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include<fstream>
#include<algorithm>
#include<iostream>
#include<vector>
#include<queue>
#define DN 50005
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
int n,m,x,y,c,a[DN],b[DN],p,ad[DN];
vector<pair<int,int> >gr[DN];
queue<int >q;
void ve()
{
    int nod;
    q.push(1);
    b[1]++;
    a[1]=0;
    while(!q.empty())
    {
        nod=q.front();
        q.pop();
        ad[nod]=0;
        for(int i=0;i<gr[nod].size();i++)
        {
            int vecin=gr[nod][i].first;
            int cost=gr[nod][i].second;
            if(a[nod]+cost<a[vecin])
            {
                a[vecin]=a[nod]+cost;
                b[vecin]++;
                if(b[vecin]==n)
                {
                    fout<<"Ciclu negativ!";
                    p=1;
                    return;
                }
                if(ad[vecin]==0)
                {
                    q.push(vecin);
                    ad[vecin]=1;
                }
            }
        }

    }

}
int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>c;
        gr[x].push_back(make_pair(y,c));
    }
    for(int i=1;i<=n;i++)
        a[i]=1000000000;
    ve();
    if(p==0)
        for(int i=2;i<=n;i++)
            fout<<a[i]<<' ';
}