Cod sursa(job #2704226)

Utilizator StefaniaIrinaDobra Stefania-Irina StefaniaIrina Data 10 februarie 2021 00:32:23
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
vector< pair<int,int> >G[50002];
queue <int> Q;
int n,m,i,j,val,oki,dist[50002],viz[50002],v[50002];
int belmanford()
{
    int x,i,cnt,j,y,cost;
    dist[1]=0;
    for(i=2;i<=n;i++)
        dist[i]=9999999;
    Q.push(1);
    v[1]=1;
    while(!Q.empty())
    {
        x=Q.front();
        viz[x]++;
        Q.pop();
        v[x]=0;
        if(viz[x]>=n)
            return 0;
        for(i=0;i<G[x].size();i++)
        {
            y=G[x][i].first;
            cost=G[x][i].second;
            if(dist[y]>dist[x]+cost)
            {
                dist[y]=dist[x]+cost;
                if(v[y]==0)
                {
                    Q.push(y);
                    v[y]=1;
                }
            }
        }
    }
    return 1;
}
int main()
{
    f>>n>>m;
    for(int k=1;k<=m;k++)
    {
        f>>i>>j>>val;
        G[i].push_back(make_pair(j,val));
    }
    if(!belmanford())
        g<<"Ciclu negativ!";
    else
    {
        for(i=2;i<=n;i++)
            g<<dist[i]<<" ";
    }
    f.close();
    g.close();
    return 0;
}