Cod sursa(job #2574744)

Utilizator federicisFedericis Alexandru federicis Data 6 martie 2020 09:35:23
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.57 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#define NMax 50001
#define oo 1<<30
using namespace std;

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

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

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

vector<pair<int,int> > muchii[NMax];
priority_queue<int, vector<int>,compara>Coada;

void Citire()
{
    in>>N>>M;
    for(int i=1;i<=M;i++)
    {
        int a,b,c;
        in>>a>>b>>c;
        muchii[a].push_back(make_pair(b,c));
    }
}

void Dijkstra(int NodStart)
{
    for(int i=1;i<=N;i++)
    {
        D[i]=oo;
    }
    D[NodStart]=0;
    Coada.push(NodStart);
    InQ[NodStart]=1;
    while(!Coada.empty())
    {   int curent=Coada.top();
    Coada.pop();
    InQ[curent]=false;
        for(unsigned int i=0;i<muchii[curent].size();i++)
        {
            int Vecin = muchii[curent][i].first;
            int Cost = muchii[curent][i].second;
            if(D[curent]+Cost<D[Vecin])
            {
                D[Vecin]=D[curent]+Cost;
                if(InQ[Vecin]==false)
                {
                    Coada.push(Vecin);
                    InQ[Vecin]=true;
                }
            }
        }
    }

}

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;
}