Cod sursa(job #2507486)

Utilizator nicoleta_mnMartin nicoleta nicoleta_mn Data 10 decembrie 2019 12:38:52
Problema Statistici de ordine Scor 50
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.7 kb
#include <fstream>

using namespace std;

ifstream cin("sdo.in");
ofstream cout("sdo.out");

int partitie(int v[],int st,int dr)
{
    swap(v[dr],v[st+rand()%(dr-st+1)]);
    int p=st;
    for(int i=st; i<dr; i++)
    {
        if(v[i]<=v[dr])
        {
            swap(v[i],v[p++]);
        }
    }
    swap(v[p],v[dr]);
    return p;
}

void qs(int v[],int st,int dr)
{
    if(st>=dr)
    {
        return;
    }
    int p=partitie(v,st,dr);
    qs(v,st,p-1);
    qs(v,p+1,dr);
}

int main()
{
    int v[500001],i,n,k;
    cin>>n>>k;
    for(i=0; i<n; i++)
    {
        cin>>v[i];
    }
    qs(v,0,n);
    for(i=1; i<=n; i++)
    {
        if(i==k)
        {
            cout<<v[k];
        }
    }
    return 0;

}