Cod sursa(job #1878652)

Utilizator TarmureSerban99Tarmure Dan Serban TarmureSerban99 Data 14 februarie 2017 12:43:33
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.37 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define inf 1522455
#define NMAX 50001

using namespace std;

ifstream f ("bellmanford.in");
ofstream fout ("bellmanford.out");

vector <pair <int, int> > g[NMAX];

int n,m,freq[NMAX],dist[NMAX],viz[NMAX];
void Bellman_Ford()
{
    for(int i=1;i<=n;i++)
        dist[i]=inf;
    queue <int> q;
    q.push(1);
    viz[1]=1;
    dist[1]=0;
    while(!q.empty())
    {
        int top=q.front();
        q.pop();
        viz[top]=0;
        for(int i=0;i<g[top].size();++i)
        {
            if(dist[g[top][i].first]>dist[top]+g[top][i].second)
                {
                    dist[g[top][i].first]=dist[top]+g[top][i].second;
                    if(viz[g[top][i].first]) continue;
                    if(++freq[g[top][i].first]>n)
                    {
                        fout<<"Ciclu negativ!";
                        return;
                    }
                    viz[g[top][i].first]=1;
                    q.push(g[top][i].first);


            }
        }
    }
    for(int i=2;i<=n;i++)
        fout<<dist[i]<<' ';
}

int main()
{
    int i,j,x,y,z;
    f>>n>>m;
    for(i=1;i<=m;++i)
    {
        f>>x>>y>>z;
        g[x].push_back(make_pair(y,z));
    }
    Bellman_Ford();



        f.close();
        fout.close();
    return 0;
}