Cod sursa(job #2590782)

Utilizator TigoanMateiTigoan Matei-Daniel TigoanMatei Data 28 martie 2020 21:31:35
Problema Algoritmul lui Dijkstra Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.59 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

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

int N, M;
int D[NMax];
bool InCoada[NMax];

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

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

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

void Dijkstra(int NodStart)
{
    for(int i = 1; i <= N; ++ i)
        D[i] = oo;

    D[NodStart] = 0;
    InCoada[NodStart] = 1;
    Coada.push(NodStart);
    while(!Coada.empty())
    {
        int NodCurent = Coada.top();
        Coada.pop();
        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])
                {
                    Coada.push(Vecin);
                    InCoada[Vecin] = 1;
                }
            }
        }
    }
}

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

int main()
{
    Citire();
    Dijkstra(1);
    Afisare();
    return 0;
}