Cod sursa(job #2588181)

Utilizator MihaiG09Gheorghe Mihai MihaiG09 Data 24 martie 2020 15:42:23
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.59 kb
#include <iostream>
#include <queue>
#include <vector>
#include <fstream>

using namespace std;

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

const int NMAX = 50001;
const int oo = (1 << 30) ;
int n, m;
int D[NMAX];
bool InCoada[NMAX];

struct ComparaDist
{
    bool operator() (int x, int y)
    {
        return D[x] > D[y];
    }
};
priority_queue <int, vector <int>, ComparaDist > Coada;
vector < pair < int, int > > v[NMAX];

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

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 NodActual = Coada.top();
        Coada.pop();
        InCoada[NodActual] = false;
        for(auto i : v[NodActual] )
        {
            int Vecin = i.first;
            int Cost = i.second;
            if(D[NodActual] + Cost < D[Vecin])
            {
                D[Vecin] = D[NodActual] + Cost;
                if(InCoada[Vecin] == false)
                {
                    Coada.push(Vecin);
                    InCoada[Vecin] = true;
                }
            }
        }
    }
}
int main()
{
    citire();
    Dijkstra(1);
    Afisare();
    return 0;
}