Cod sursa(job #1659424)

Utilizator andru47Stefanescu Andru andru47 Data 22 martie 2016 10:45:54
Problema Statistici de ordine Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.6 kb
#include <bits/stdc++.h>
using namespace std;
int n,k,v[3000000 + 5];
inline void rec(int st,int dr,int pos)
{
    if (st>dr)return ;
    swap(v[dr],v[st+rand()%(dr-st+1)]);
    int piv = v[dr],j = st - 1;
    for (int i = st; i<=dr; ++i)
    if (v[i]<=piv)swap(v[i],v[++j]);
    if (j>pos)rec(st,j-1,pos);
    else rec(j+1,dr,pos);
}
int main()
{
    freopen("sdo.in","r",stdin);
    freopen("sdo.out","w",stdout);
    scanf("%d %d\n", &n, &k);
    for (int i = 1; i<=n; ++i)
        scanf("%d", &v[i]);
    //srand(time(0));
    rec(1, n, k);
    printf("%d\n", v[k]);
    return 0;
}