Cod sursa(job #2777912)

Utilizator fredtuxFlorin Dinu fredtux Data 26 septembrie 2021 00:06:56
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.47 kb
#include <fstream>
#include <vector>
#include <queue>
#include <climits>

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

const int NMax = 50005;

int N, M;
vector<int> D(NMax, INT_MAX);
vector<bool> InCoada(NMax);

vector < pair <int, int> > G[NMax];

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

priority_queue <int, vector<int>, comparaDistante> Coada;

void Citeste(){
    fin >> N >> M;
    for(int i = 1; i <= M; i++){
        int x, y, c;
        fin >> x >> y >> c;
        G[x].push_back(make_pair(y, c));
    }
}

void Afiseaza(){
    for(int i = 2; i <= N; i++){
        if(D[i] != INT_MAX)
            fout << D[i] << " ";
        else
            fout << "0 ";
    }
}

void Dijkstra(int nodStart){
    D[nodStart] = 0;
    Coada.push(nodStart);
    InCoada[nodStart] = true;

    while(!Coada.empty()){
        int nodCurent = Coada.top();
        Coada.pop();
        InCoada[nodCurent] = false;

        for(unsigned int i = 0; i < G[nodCurent].size(); i++){
            int Vecin = G[nodCurent][i].first;
            int Cost = G[nodCurent][i].second;
            if(D[nodCurent] + Cost < D[Vecin]){
                D[Vecin] = D[nodCurent] + Cost;
                if(InCoada[Vecin] == false){
                    Coada.push(Vecin);
                    InCoada[Vecin] = true;
                }
            }
        }
    }
}

int main(){
    Citeste();
    Dijkstra(1);
    Afiseaza();

    return 0;
}