Cod sursa(job #3190747)

Utilizator Edyci123Bicu Codrut Eduard Edyci123 Data 7 ianuarie 2024 21:38:23
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.12 kb
#include <fstream>
#include <vector>
#include <set>

#define DIM 50005
#define INF 0x3f3f3f3f

using namespace std;

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

int n, m;
vector<pair<int, int>> edges[DIM];
set<pair<int, int>> s;
int d[DIM];

void dijkstra(int startNode) {
    s.insert({0, startNode});
    for (int i = 1; i <= n; i++) {
        d[i] = INF;
    }
    d[startNode] = 0;

    while (!s.empty()) {
        int node = s.begin()->second;
        s.erase(s.begin());
        for (auto child : edges[node]) {
            if (d[child.first] > d[node] + child.second) {
                s.erase({d[child.first], child.first});
                d[child.first] = d[node] + child.second;
                s.insert({d[child.first], child.first});
            }
        }
    }
}

int main() {

    f >> n >> m;

    for (int i = 0; i < m; i++) {
        int x, y, cost;
        f >> x >> y >> cost;
        edges[x].emplace_back(y, cost);
    }

    dijkstra(1);

    for (int i = 2; i <= n; i++) {
        if (d[i] == INF) {
            g << 0 << " ";
        } else {
            g << d[i] << " ";
        }
    }

    return 0;
}