Cod sursa(job #3319501)

Utilizator PatrikKev75Szucs Patrik - Kevin PatrikKev75 Data 1 noiembrie 2025 17:17:47
Problema Algoritmul Bellman-Ford Scor 15
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.23 kb
// https://www.infoarena.ro/problema/bellmanford - Szücs Patrik - Kevin
#include <fstream>
#include <vector>
#include <climits>

struct edge
{
    int from, to, price;
};

int main()
{
    std::ifstream in("bellmanford.in");
    std::ofstream out("bellmanford.out");

    int n, m;
    in >> n >> m;

    std::vector<edge> edges(m);
    for (int i = 0; i < m; i++)
        in >> edges[i].from >> edges[i].to >> edges[i].price;

    in.close();

    std::vector<int> dist(n + 1, INT_MAX);
    dist[1] = 0;

    // Bellman-Ford
    bool changed;
    for (int i = 1; i < n; i++)
    {
        changed = false;
        for (auto &e : edges)
            if (dist[e.from] != INT_MAX && dist[e.from] + e.price < dist[e.to])
            {
                dist[e.to] = dist[e.from] + e.price;
                changed = true;
            }
        if (!changed)
            break; // gyorsítás
    }

    for (auto &e : edges)
        if (dist[e.from] != INT_MAX && dist[e.from] + e.price < dist[e.to])
        {
            out << "Ciclu negativ\n";
            return 0;
        }

    for (int i = 2; i <= n; i++)
        out << (dist[i] == INT_MAX ? 0 : dist[i]) << ' ';

    out.close();
    return 0;
}