Cod sursa(job #2605172)

Utilizator MerlinTheWizardMelvin Abibula MerlinTheWizard Data 24 aprilie 2020 16:08:16
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include<iostream>
#include<fstream>
#include<queue>
#include<vector>
using namespace std;
int n;
int ap[50001];
int modif[50001];
int rasp[50001];
vector<pair<int,int> >muchii[250001];
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
void bellman_ford()
{
    int inf=1000000000;
    for(int i = 1; i <= n; ++i)
        rasp[i] = inf;
    queue<int>q;
    q.push(1);
    rasp[1] = 0;
    ap[1] = 1;
    while(!q.empty())
    {
        int nod = q.front();
        q.pop();
        ap[nod] = 0;
        for(auto it : muchii[nod])
        {
            if(rasp[it.first] > rasp[nod] + it.second)
            {
                rasp[it.first] = rasp[nod] + it.second;
                if(ap[it.first] == 0)
                {
                    q.push(it.first);
                    ap[it.first] = 1;
                }
                modif[it.first]++;
                if(modif[it.first] > n)
                {
                    g <<"Ciclu negativ!";
                    return;
                }
            }
        }
    }
    for(int i = 2; i <= n; ++i)
        g << rasp[i] << " ";
}
int main()
{
    int m;
    f >> n >> m;
    while(m--)
    {
        int x,y,cost;
        f >> x >> y >> cost;
        muchii[x].push_back({y,cost});
    }
    bellman_ford();
}