Cod sursa(job #2158517)

Utilizator JiyuuNoTsubasaMaria Guran JiyuuNoTsubasa Data 10 martie 2018 13:39:40
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.29 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
vector <pair<int,int> > v[250005];
queue <int> coada;
int d[50005],inqueue[50005],n,m,nr[50005];
const int inf=100000;
int main()
{
    int x,y,c;
    in>>n>>m;
    for (int i=1; i<=m; i++)
    {
        in>>x>>y>>c;
        v[x].push_back(make_pair(y,c));
    }
    for (int i=2; i<=n; i++)
        d[i]=inf;
    d[1]=0;
    coada.push(1);
    inqueue[1]=1;
    while (!coada.empty())
    {
        int vf=coada.front();
        coada.pop();
        inqueue[vf]=0;
        for (int i=0; i<v[vf].size(); i++)
            if (d[vf]+v[vf][i].second<d[v[vf][i].first])
            {
                d[v[vf][i].first]=d[vf]+v[vf][i].second;
                if (inqueue[v[vf][i].first]==0)
                {
                    coada.push(v[vf][i].first);
                    inqueue[v[vf][i].first]=1;
                    nr[v[vf][i].first]++;
                    if(nr[v[vf][i].first]==n)
                    {
                        out<<"Ciclu negativ!";
                        return 0;
                    }
                }
            }
    }
    for(int i=2; i<=n; i++)
    {
        out<<d[i]<<" ";
    }
    return 0;
}