Cod sursa(job #2566072)

Utilizator CarlaDianaCarla Diana CarlaDiana Data 2 martie 2020 18:40:24
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define inf 250000000
using namespace std;
ifstream fin ("bellmanford.in");
ofstream fout ("bellmanford.out");
vector <pair<int,int> >v[50010];
queue <int> q;
int n,m,a,b,c,d[50010];
int main()
{
    fin>>n>>m;
    for(;m;m--)
    {
        fin>>a>>b>>c;
        v[a].push_back(make_pair(c,b));
       /// v[b].push_back(make_pair(c,a));
    }
    for(int i=1;i<=n;i++)
        d[i]=inf;
    q.push(1);
    d[1]=0;
    ///int i=0;&&i<n
    while(!q.empty())
    {
        ///i++;
        for(auto it:v[q.front()])
        {
            if(d[q.front()]+it.first<d[it.second]&&it.second!=1)
            {
                d[it.second]=d[q.front()]+it.first;
                q.push(it.second);
            }
        }
        q.pop();
    }


    for(int i=2;i<=n;i++)
    {
         for(auto it:v[i])
         {
             if(it.second==1)
             {
                 if(d[i]+it.first<0)
                 {
                     fout<<"Ciclu negativ!";
                     return 0;
                 }
             }
         }
    }
    for(int i=2;i<=n;i++)
        fout<<d[i]<<" ";
    return 0;
}