Cod sursa(job #2175606)

Utilizator adimiclaus15Miclaus Adrian Stefan adimiclaus15 Data 16 martie 2018 18:02:23
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define INF 0x3f3f3f3f
using namespace std;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
vector < pair<int,int> > a[50001];
queue <int> coada;
int n,m,viz[50001],d[50001],x,y,c,i,nod,nr[50001];
int main()
{
    f>>n>>m;
    while(m--)
    {
        f>>x>>y>>c;
        a[x].push_back(make_pair(y,c));
    }
    for(i=1;i<=n;i++)
    {
        viz[i]=0;
        nr[i]=0;
        d[i]=INF;
    }
    d[1]=0;
    coada.push(1);
    viz[1]=1;
    while(!coada.empty())
    {
        nod=coada.front();
        coada.pop();
        viz[nod]=0;
        for(i=0;i<a[nod].size();i++)
        {
            if(d[a[nod][i].first]>d[nod]+a[nod][i].second)
            {
                d[a[nod][i].first]=d[nod]+a[nod][i].second;
                if(viz[a[nod][i].first]==0)
                {
                    coada.push(a[nod][i].first);
                    viz[a[nod][i].first]=1;
                    nr[a[nod][i].first]++;
                    if(nr[a[nod][i].first]>n)
                    {
                        g<<"Ciclu negativ!";
                        return 0;
                    }
                }
            }
        }
    }
    for(i=2;i<=n;i++)
        g<<d[i]<<" ";
    return 0;
}