Cod sursa(job #2582447)

Utilizator razvan1403razvan razvan1403 Data 16 martie 2020 19:00:52
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.49 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

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

const int NMax=50005;
const int oo = (1 << 30);

int n,m;
int D[NMax];
bool InCoada[NMax];

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

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

priority_queue < int, vector < int >, compara> 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 Dijkstra(int nod_start)
{
    for(int i=1;i<=n;i++)
        D[i]=oo;

    D[nod_start] = 0;
    Coada.push(nod_start);
    InCoada[nod_start] = 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;
                }

            }
        }
    }

}


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

int main()
{
    Citeste();
    Dijkstra(1);
    Afiseaza();
    return 0;
}