Cod sursa(job #2372057)

Utilizator Anastasia11Susciuc Anastasia Anastasia11 Data 6 martie 2019 21:07:44
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.05 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define Nmax 50005
#define INF 0x3f3f3f3f

using namespace std;

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

int n, m, x, y, c;
int cnt[Nmax], d[Nmax];
vector <pair <int, int> > v[Nmax];
queue <int> Q;

int main()
{
    f >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        f >> x >> y >> c;
        v[x].push_back({y, c});
    }
    for (int i = 1; i <= n; i++) d[i]=INF;

    Q.push(1);
    d[1]=0;
    while(!Q.empty())
    {
        int x=Q.front();
        Q.pop();
        for (auto i:v[x])
        {
            int y=i.first;
            int c=i.second;
            if(d[x]+c < d[y])
            {
                d[y]=d[x] +c;
                cnt[y]++;
                if(cnt[y] > n)
                {
                    g << "Ciclu negativ!";
                    return 0;
                }
                Q.push(y);
            }
        }
    }
    for (int i = 2; i <= n; i++) g << d[i] << " ";

    return 0;
}