Cod sursa(job #3270956)

Utilizator tobiasSpartanu89Rosianu Radu tobiasSpartanu89 Data 24 ianuarie 2025 21:49:45
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.26 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <climits>

std::ifstream f("dijkstra.in");
std::ofstream g("dijkstra.out");

const int NMAX = 1e5;
std::vector<std::pair<int, int>> L[NMAX + 1]; // Lista de adiacență cu (vecin, cost)
int N, M, start, finish;
int dist[NMAX + 1], tata[NMAX + 1];

void dijkstra() {
    std::priority_queue<std::pair<int, int>, std::vector<std::pair<int, int>>, std::greater<>> pq;

    dist[start] = 0;
    pq.emplace(0, start);

    while (!pq.empty()) {
        int d = pq.top().first;
        int at = pq.top().second;
        pq.pop();

        if (d > dist[at]) continue;

        for (auto [to, cost] : L[at]) {
            if (dist[at] + cost < dist[to]) {
                dist[to] = dist[at] + cost;
                tata[to] = at;
                pq.emplace(dist[to], to);
            }
        }
    }

}

int main() {
    f >> N >> M;

    for (int i = 1; i <= M; ++i) {
        int x, y, cost;
        f >> x >> y >> cost;
        L[x].emplace_back(y, cost);
//        L[y].push_back({x, cost});
    }


    std::fill(dist, dist + N + 1, INT_MAX);
    start = 1;

    dijkstra();


    for (int i = 2; i <= N; ++i){
        int d = (dist[i] == INT_MAX) ? 0 : dist[i];
        g << d << " ";
    }

    return 0;
}