Cod sursa(job #2399502)

Utilizator CristyXtremeSimion Cristian CristyXtreme Data 7 aprilie 2019 17:16:48
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.24 kb
#include <iostream>
#include <vector>
#include <queue>
#include <fstream>
using namespace std;
#define inf 0x3f3f3f3f

typedef pair<int, int> ipair;

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

vector<vector<ipair>> v(50001);

vector<int> dijkstra(int s, int n) {
    vector<int> d(n + 1, inf), t(n + 1, 0);
    priority_queue<ipair, vector<ipair>, greater<ipair>> Q;
    d[s] = 0;
    Q.push({0, s});
    while(!Q.empty()){
        auto nod = Q.top();
        Q.pop();
        if (d[nod.second] != nod.first)
            continue;
        for(auto&& vecin : v[nod.second]) {
            int cost = vecin.first, next = vecin.second;
            if (d[next] > d[nod.second] + cost) {
                d[next] = d[nod.second] + cost;
                Q.push({d[next], next});
            }
        }     
    }
    return d;
}

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});
    }
    vector<int> sol = dijkstra(1, n);
    for (int i = 2; i <= n; i++) {
        if (sol[i] == inf) {
            out << "0 ";
        }
        else {
            out << sol[i] << " ";
        }
    }
    return 0;
}