Cod sursa(job #2350046)

Utilizator Ioni2001Ion Patroescu Ioni2001 Data 20 februarie 2019 23:20:27
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.53 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

const int NMax = 50007;
const int oo = (1 << 30);

int N,M;
int D[NMax];

bool InCoada[NMax];

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

vector < pair <int , int> > G[NMax];
priority_queue <int, vector < int > , comparaDistante> Coada;

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

void Dijkstra(int nodStart)
{
    for(int i=1;i<=N;i++)
        D[i]=oo;
    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()
{
    citire();
    Dijkstra(1);
    afisare();
}