Cod sursa(job #3213190)

Utilizator tudorhorotanHorotan Tudor tudorhorotan Data 12 martie 2024 17:39:13
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.7 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

const int NLIM = 50001;
const int oo = (1 << 30);
bool inCoada[NLIM];
int distanta[NLIM], n, m;

vector < pair <int, int > > muchii_lg[NLIM];

struct comparareDistante {
    bool operator ()(int x, int y) {
        return distanta[x] > distanta[y];
    }
};

priority_queue < int, vector < int >, comparareDistante > coada;

void Citire(){
    fin >> n >> m;
    for (int i = 1; i <= m ; ++i) {
        int x, y, lg;
        fin >> x >> y >> lg;
        muchii_lg[x].push_back(make_pair(y, lg));
    }
}

void Dijkstra(int nodStart) {
    for (int i = 1; i <= n; ++i) {
        distanta[i] =oo;
    }
    distanta[nodStart] = 0;

    inCoada[nodStart] = 1;
    coada.push(nodStart);

    while(coada.size() > 0) {
        int nod = coada.top();
        coada.pop();
        inCoada[nod] = 0;

        for (int i = 0; i < muchii_lg[nod].size(); ++i) {
            int vecin = muchii_lg[nod][i].first;
            int lungime = muchii_lg[nod][i].second;
            if(distanta[vecin] > distanta[nod] + lungime) {
                distanta[vecin] = distanta[nod] + lungime;
                if(inCoada[vecin] == 0) {
                    coada.push(vecin);
                    inCoada[vecin] = 1;
                }
            }
        }
    }
}

void Afisare () {
    for (int i = 2; i <= n; ++i) {
        if (distanta[i] != oo) {
            fout << distanta[i] << " ";
        } else {
            fout << "0 ";
        }
    }
}

int main()
{
    Citire();
    Dijkstra(1);
    Afisare();
    return 0;
}