Cod sursa(job #1185747)

Utilizator radu_cebotariRadu Cebotari radu_cebotari Data 16 mai 2014 18:42:32
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.64 kb
#include<fstream>
#include<vector>
#include<queue>
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");

const int INFINIT = 200000000;
vector <int> v[50009];
vector <int> cost[50009];
queue<int> coada;
int viz[50009],c[50009],sol[50009],n,m,K;

int bmf(int start)
{
    int aparitii[50009];
    coada.push(start);
    int i;
    for(i = 1 ; i <= n ; i++){
        sol[i] = INFINIT;
        aparitii[i] = 0;
    }
    viz[start] = 1;
    sol[1] = 0;
    aparitii[start]++;
    while(!coada.empty())
    {
        viz[coada.front()] = 0;
        for(i = 0 ; i < v[coada.front()].size() ; i++)
        {

            if(sol[coada.front()] < INFINIT){
                if(sol[v[coada.front()][i]] > sol[coada.front()] + cost[coada.front()][i]){
                    sol[v[coada.front()][i]] = sol[coada.front()] + cost[coada.front()][i];
                    if(viz[v[coada.front()][i]] == 0){
                        viz[v[coada.front()][i]] = 1;
                        if(aparitii[v[coada.front()][i]] > n)
                            return 0;
                        aparitii[v[coada.front()][i]]++;
                        coada.push(v[coada.front()][i]);
                    }
                }

            }
        }
        coada.pop();
    }
    return 1;
}

int main()
{


    int i,x,y;
    in>>n>>m;
    for(i = 1 ; i <= m ; i++)
    {

        in>>x>>y>>K;
        v[x].push_back(y);
        cost[x].push_back(K);
    }
    if(bmf(1) == 0)
        out<<"Ciclu negativ!";
    else{
        for(i = 2 ; i <= n ; i++)
            out<<sol[i]<<" ";
    }
    return 0;
}