Cod sursa(job #2425559)

Utilizator CristyXtremeSimion Cristian CristyXtreme Data 24 mai 2019 21:33:36
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

vector <vector <pair <int, int> > > v(50001);

void dijkstra(int s, int n) {
    vector <int> d(n + 1, 0x3f3f3f3f);
    priority_queue <pair <int, int>, vector <pair <int, int> >, greater <pair <int, int> > > Q;

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

    while (!Q.empty) {
        auto curent = Q.top();
        int cdist = curent.first;
        int cnod = curent.second;
        Q.pop();

        if (d[cnod] != cdist)
            continue;
        
        for (auto el : v[cnod]) {
            int ndist = el.first;
            int nnod = el.second;

            if (d[nnod] > ndist + cdist) {
                d[nnod] = ndist + cdist;
                Q.push({d[nnod], nnod});
            }
        }
    }

    for (unsigned i = 2; i < d.size(); i++)
        if (d[i] == 0x3f3f3f3f)
            out << 0 << ' ';
        else
            out << d[i] << ' ';
}

int main() {
    int n, m;
    int a, b, c;

    in >> n >> m;
    for (int i = 0; i < m; i++) {
        in >> a >> b >> c;
        v[a].push_back({c, b});
        v[b].push_back({c, a});
    }

    dijkstra(1, n);
    return 0;
}