Cod sursa(job #2136683)

Utilizator albucristianAlbu Cristian-Gabriel albucristian Data 20 februarie 2018 09:35:26
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.24 kb
#include <bits/stdc++.h>
using namespace std;
vector <pair<int,int> > g[50004];
queue <int> coada;
int d[50002],viz[50002];
bool inq[50002];
int n,m,x,y,z,f;
int bellmanford(int start)
{
    int nod,cost,fiu;
    coada.push(start);
    viz[start]++;
    inq[start]=1;
    while(!coada.empty())
    {
        nod=coada.front();
        coada.pop();
        inq[nod]=0;
        for(int i=0;i<g[nod].size();i++)
        {
            fiu=g[nod][i].first;
            cost=g[nod][i].second;
            if(d[fiu]>d[nod]+cost)
            {
                d[fiu]=d[nod]+cost;
                coada.push(fiu);
                viz[fiu]++;
                if(viz[fiu]>n)
                    return 1;
                inq[fiu]=1;
            }
        }
    }
    return 0;
}
int main()
{
    ifstream in("bellmanford.in");
    ofstream out("bellmanford.out");
    in>>n>>m;
    for(int i=1;i<=m;i++)
    {
        in>>x>>y>>z;
        g[x].push_back(make_pair(y,z));
    }
    for(int i=2;i<=n;i++)
    {
        d[i]=1000000;
    }
    f=bellmanford(1);
    if(f==1)
        out<<"Ciclu negativ!";
    else
    {
        for(int i=2;i<=n;i++)
        {
            out<<d[i]<<" ";
        }
    }
    return 0;
}