Cod sursa(job #3190533)

Utilizator Pop_AlexandruPop Alexandru Pop_Alexandru Data 7 ianuarie 2024 18:02:47
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.18 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

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

#define NMAX 100005
#define INF 1000000000

vector<pair<int, int>> G[NMAX];
priority_queue<pair<int, int>> PQ;
int dist[NMAX];
bool viz[NMAX];

void dijkstra(int start, int n) {
    for (int i = 1; i <= n; ++i) {
        dist[i] = INF;
    }

    dist[start] = 0;
    PQ.push({0, start});
    while (PQ.size()) {
        int nod = PQ.top().second;
        PQ.pop();

        if (!viz[nod]) {
            viz[nod] = 1;

            for (auto it : G[nod]) {
                if (dist[it.first] > dist[nod] + it.second) {
                    dist[it.first] = dist[nod] + it.second;
                    PQ.push({-dist[it.first], it.first});
                }
            }
        }
    }
}

int main() {
    int n, m;
    fin >> n >> m;
    while (m--) {
        int a, b, c;
        fin >> a >> b >> c;
        G[a].push_back({b, c});
    }

    dijkstra(1, n);

    for (int i = 2; i <= n; ++i) {
        if (dist[i] == INF) {
            dist[i] = 0;
        }

        fout << dist[i] << ' ';
    }
    return 0;
}