Cod sursa(job #3326705)

Utilizator AlexN_04Nedelcu Alex AlexN_04 Data 30 noiembrie 2025 00:51:50
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.32 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

#define INF 1e9

ifstream fin("files/dijkstra.in");
ofstream fout("files/dijkstra.out");

vector<int> d;

void dijkstra(int s, vector<vector<pair<int, int>>> &la, int N) {
    vector<int> tata(N + 1, 0);
    vector<int> viz(N + 1, 0);

    d.assign(N + 1, INF);

    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;

    d[s] = 0;
    pq.push({d[s], s});

    while(!pq.empty()) {
        pair<int, int> crt = pq.top();
        pq.pop();

        if (viz[crt.second] == 1)
            continue;
        viz[crt.second] = 1;
        
        for (auto& vecin : la[crt.second]) {
            int cost = vecin.first;
            int nod = vecin.second;

            if (d[crt.second] + cost < d[nod]) {
                d[nod] = d[crt.second] + cost;
                tata[nod] = crt.second;
                pq.push({d[nod], nod});
            }
        }
    }
}
int main() {
    int N, M;
    fin >> N >> M;

    vector<vector<pair<int, int>>> la(N + 1);

    for (int i = 0; i < M; i++) {
        int x, y, w;
        fin >> x >> y >> w;
        
        la[x].push_back({w,y});
    }

    dijkstra(1, la, N);

    for (int i = 2; i <= N; i++) {
        fout << (d[i] == INF ? 0 : d[i]) << ' ';
    }

    return 0;
}