Cod sursa(job #1908575)

Utilizator NuamcontJohn George Nuamcont Data 7 martie 2017 09:28:44
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.28 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define oo 999999999
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
vector < vector < pair <int, int> > > v;
vector <int> d;
queue <int> q;
bool viz[50001];
int a[50001];
int n, m, k;
int main()
{
    fin>>n>>m;
    int x, y, z;
    d.resize(n + 1, oo);
    v.resize(n + 1);
    for (int i = 1; i <= m; i++) {
        fin>>x>>y>>z;
        v[x].push_back(make_pair(y, z));
    }
    int R = 1;
    d[R] = 0;
    q.push(R);
    while (!q.empty()) {
        k = q.front();
        q.pop();
        viz[k] = false;
        for (int i = 0; i < v[k].size(); i++) {
            y = v[k][i].first;
            if(d[y] > v[k][i].second + d[k]) {
                d[y] = v[k][i].second + d[k];
                if (viz[v[k][i].first] == false) {
                    viz[v[k][i].first] = true;
                    q.push(y);
                    a[y]++;
                    if(a[y]>n) {
                        fout<<"Ciclu negativ!";
                        return 0;
                    }
                }
            }
        }
    }
    for (int i = 2; i <= n; i++) {
        fout<<d[i]<<' ';
    }
    fin.close();
    fout.close();
    return 0;
}