Cod sursa(job #2756307)

Utilizator filicriFilip Crisan filicri Data 30 mai 2021 18:43:15
Problema Algoritmul lui Dijkstra Scor 10
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.12 kb
#include <fstream>
#include <vector>
#include <queue>
#include <climits>
#define N_MAX 50001

using namespace std;

int main() {
    ifstream f("dijkstra.in");
    int n, m;
    vector<pair<int, int>> G[N_MAX];
    f >> n >> m;
    for (int i = 0; i < n; i++) {
        int x, y, c;
        f >> x >> y >> c;
        G[x].push_back({y, c});
    }
    f.close();

    int dist[n + 1];
    bool seen[n + 1];
    dist[1] = 0;
    seen[1] = false;
    for (int i = 2; i <= n; i++) {
        dist[i] = INT_MAX;
        seen[i] = false;
    }

    priority_queue<pair<int, int>> pq;
    pq.push({0, 1});
    while (!pq.empty()) {
        int node = pq.top().second;
        pq.pop();
        if (seen[node])
            continue;
        seen[node] = true;
        for (const auto& ne: G[node]) {
            if (dist[ne.first] > dist[node] + ne.second) {
                dist[ne.first] = dist[node] + ne.second;
                pq.push({-dist[ne.first], ne.first});
            }
        }
    }

    ofstream g("dijkstra.out");
    for (int i = 2; i <= n; i++)
        g << (dist[i] == INT_MAX ? 0 : dist[i]) << ' ';
    g.close();
    return 0;
}