Cod sursa(job #2772396)

Utilizator oana_tosa15Tosa Oana-Miruna oana_tosa15 Data 1 septembrie 2021 00:27:11
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.57 kb
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

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

const int NMax=50008;
const int oo = (1 << 30);

int n,m;
int D[NMax];
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 Read()
{
    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]!=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(size_t 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()
{
    Read();
    Dijkstra(1);
    Afiseaza();
    return 0;
}