Cod sursa(job #2466173)

Utilizator sichetpaulSichet Paul sichetpaul Data 1 octombrie 2019 17:46:08
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.01 kb
#include <bits/stdc++.h>
#define Nmax 50005
#define INF 2e9
using namespace std;

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

int N, M;
vector<pair<int, int> > G[Nmax];
queue<int> Q;
int dist[Nmax], nr[Nmax];
int main()
{
    f >> N >> M;
    for (int i = 1; i <= M; ++i) {
        int x, y, d;
        f >> x >> y >> d;
        G[x].push_back({y, d});
    }

    for (int i = 2; i <= N; ++i)
        dist[i] = INF;

    Q.push(1);
    while (!Q.empty()) {
        int node = Q.front();
        Q.pop();

        for (auto it: G[node])
        if (dist[it.first] > dist[node] + it.second) {
              int node2 = it.first, D = it.second;
              ++nr[node2];
              if (nr[node2] == N) {
                   g << "Ciclu negativ!\n";
                   return 0;
              }

              dist[node2] = dist[node] + D;
              Q.push(node2);
        }
    }

    for (int i = 2; i <= N; ++i)
        g << dist[i] << " ";

    return 0;
}