Cod sursa(job #2563381)

Utilizator denmirceaBrasoveanu Mircea denmircea Data 1 martie 2020 11:08:06
Problema Statistici de ordine Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.61 kb
#include <bits/stdc++.h>
#define dim 3000005
using namespace std;
ifstream fin("sdo.in");
ofstream fout("sdo.out");
int v[dim],n,k,i,mid,j;
void qs(int st,int dr,int k)
{
    if(st==dr)
        return;
    mid=v[((1ll*rand()*rand())%(dr-st+1))+st];
    j=st-1;
    for(int i=st; i<=dr; i++)
    {
        if(v[i]<=mid)
            swap(v[++j],v[i]);
    }
    if(j-st+1<k)
        qs(j+1,dr,k-(j-st+1));
    else
        qs(st,j,k);

}
int main()
{
    ios_base::sync_with_stdio(false);
    fin>>n>>k;
    for(i=1; i<=n; i++)
    {
        fin>>v[i];
    }
    qs(1,n,k);
    fout<<v[k];
}