Cod sursa(job #1212701)

Utilizator mariusn01Marius Nicoli mariusn01 Data 25 iulie 2014 17:05:47
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.16 kb
#include <fstream>
#include <vector>
#include <queue>
#include <bitset>

#define DIM 50010
#define INF 1000000000

using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");

vector< pair< int, int > > L[DIM];
queue<int> q;
bitset<DIM> v;
int D[DIM], N[DIM];

int n, m, i, x, y, z;

int main() {
    fin>>n>>m;
    for (i=1;i<=m;i++) {
        fin>>x>>y>>z;
        L[x].push_back(make_pair(y, z));
    }

    q.push(1);
    v[1] = 1;
    D[1] = 0;
    for (i=2;i<=n;i++)
        D[i] = INF;

    while(!q.empty()) {
        x = q.front();
        q.pop();
        v[x] = 0;

        for (i=0;i<L[x].size();i++) {
            y = L[x][i].first;
            if (D[y] > D[x] + L[x][i].second) {
                D[y] = D[x] + L[x][i].second;
                N[y]++;
                if (N[y] == n) {
                    fout<<"Ciclu negativ!";
                    return 0;
                }
                if (!v[y]) {
                    q.push(y);
                    v[y] = 1;
                }
            }
        }


    }

    for (i=2;i<=n;i++)
        fout<<D[i]<<" ";

    return 0;
}