Cod sursa(job #2802866)

Utilizator RoboRobert Vaslaru Robo Data 18 noiembrie 2021 22:38:51
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.29 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

typedef pair<int, int> ii;

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

void dijkstra(vector<vector<pair<int, int>>>& ad, int n, int s) {
   
    const int INF = 0x3f3f3f3f;
    
    vector<int> dist(n + 1, INF);
    vector<bool>viz(n + 1, false);
    priority_queue<ii, vector<ii>, greater<ii>> vec;

    dist[1] = 0;
    vec.push({ 0, 1 });

    while (!vec.empty()) {
        int nod = vec.top().second;
        vec.pop();

        if (!viz[nod]) {
            viz[nod] = true;

            for (auto v : ad[nod]) {
                if (dist[nod] + v.second < dist[v.first]) {
                    dist[v.first] = dist[nod] + v.second;
                    vec.push({ dist[v.first], v.first });
                }
            }
        }
    }

    for (int i = 2; i <= n; ++i) {
        if (dist[i] != INF) {
            out << dist[i] << ' ';
        }
        else {
            out << "0 ";
        }
    }
}

int main() {

    int n, m, x, y, cost;
    in >> n >> m;

    vector<vector<ii>> ad(n + 1);

    for (int i = 1; i <= m; ++i) {
        in >> x >> y >> cost;
        ad[x].push_back({ y, cost });
    }


    dijkstra(ad, n, 1);

    return 0;
}