Cod sursa(job #1921787)

Utilizator Emil64Emil Centiu Emil64 Data 10 martie 2017 14:24:44
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.13 kb
#include <bits/stdc++.h>
#define oo (1<<30)

using namespace std;

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

vector< pair<int, int> >v[50001];
int n, m;
bool viz[50001]={false};
queue<int> q;
int nr[50001]={0};
int sol[50001];

int main(){

    int i, j, a, b, c;
    f >> n >> m;
    for(i=1; i<=m; i++){
        f >> a >> b >> c;
        v[a].push_back(make_pair(b, c));

    }
    for(i=2; i<=n; i++)
        sol[i] = oo;
    q.push(1);
    nr[1] = 1;
    while(!q.empty()){

        a = q.front();
        q.pop();
        viz[a] = false;
        for(i=0; i<v[a].size(); i++)
            if(sol[v[a][i].first] > sol[a] + v[a][i].second){
                sol[v[a][i].first] = sol[a] + v[a][i].second;
                if(!viz[v[a][i].first]){
                    viz[v[a][i].first] = true;
                    q.push(v[a][i].first);
                    nr[v[a][i].first]++;
                    if(nr[v[a][i].first] >= n){
                        g << "Ciclu negativ!\n";
                        return 0;
                    }
                }
            }
    }
    for(i=2; i<=n; i++)
        g << sol[i] << " ";
    g << "\n";
}