Cod sursa(job #2755566)

Utilizator George_CristianGeorge Dan-Cristian George_Cristian Data 27 mai 2021 18:01:53
Problema Algoritmul lui Dijkstra Scor 50
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include <fstream>
#include <vector>
#include <bitset>

using namespace std;

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

#define NMAX 50005
#define INF 1000000000

int n, m;
vector<pair<int, int>> G[NMAX];
int d[NMAX], t[NMAX];
bitset<NMAX> viz;

void citire() {
    f >> n >> m;
    int nod1, nod2, cost;
    for (int i = 0; i < m; i++) {
        f >> nod1 >> nod2 >> cost;
        G[nod1].push_back({cost, nod2});
    }
}

void initializare() {
    for (int i = 2; i <= n; i++)
        d[i] = INF;
}

void parcurgere() {
    int vf = 1;
    while (vf) {
        viz[vf] = true;
        for (auto &nod:G[vf])
            if (!viz[nod.second] && d[vf] + nod.first < d[nod.second]) {
                d[nod.second] = d[vf] + nod.first;
                t[nod.second] = vf;
            }
        int mini = INF;
        vf = 0;
        for (int i = 1; i <= n; i++)
            if (!viz[i] && d[i] < mini) {
                mini = d[i];
                vf = i;
            }
    }
}

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

int main() {
    citire();
    initializare();
    parcurgere();
    afisare();
    return 0;
}