Cod sursa(job #3212722)

Utilizator RatebaSerbanescu Andrei Victor Rateba Data 12 martie 2024 09:17:54
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.59 kb
#include <fstream>
#include <queue>
#include <vector>

#define INF 2e9

using namespace std;

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

struct t_muchie {
    int nod;
    int cost;

    bool operator<(const t_muchie& other) const {
        return cost > other.cost;
    }
};

const int MAX_N = 50001;

int main() {

    int n, m;
    vector<t_muchie> vecini[MAX_N];
    int drum[MAX_N];
    bool viz[MAX_N] = {0};

    fin >> n >> m;

    for (int i = 1; i <= m; i++) {
        int nod1, nod2, cost;
        fin >> nod1 >> nod2 >> cost;
        t_muchie muchie = {nod2, cost};
        vecini[nod1].push_back(muchie);
    }

    for (int i = 1; i <= n; i++) {
        drum[i] = INF;
    }
    drum[1] = 0;
    viz[1] = true;

    priority_queue<pair<int, int> > pq;
    pair p = {0, 1};
    pq.push(p);

    while (!pq.empty()) {
        int nod_curr = pq.top().second;
        pq.pop();

        for (int i = 0; i < vecini[nod_curr].size(); i++) {
            int vecin = vecini[nod_curr][i].nod;
            int cost  = vecini[nod_curr][i].cost;

            if (!viz[vecin] && drum[vecin] > drum[nod_curr] + cost) {
                viz[vecin] = true;
                drum[vecin] = drum[nod_curr] + cost;
                
                pair p_vecin = {-drum[vecin], vecin};
                pq.push(p_vecin);
            }
        }
    }

    for (int i = 2; i <= n; i++) {
        if (drum[i] == INF) {
            fout << "0 ";
        } else {
            fout << drum[i] << ' ';
        }
    }
    // for (int i = 1; i <= n; i++) {
    //     fout << i << ' ' << drum[i] << endl;
    // }

    return 0;
}