#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
int n,m,k=0,hh[1001],y,ass;
bool compare(int a,int b)
{
  return a>b; //升序排列，如果改为return a>b，则为降序
} 
int main(){
	freopen("mark.in","r",stdin);
	freopen("mark.out","w",stdout);
	cin>>n>>m;
	for(int i=1;i<=n;i++)
		cin>>hh[i];
	cin>>y;
	ass=hh[y];
	sort(hh+1,hh+n,compare);
	for(int i=1;i<=n;i++)
	{
		if(ass==hh[i]){
			y=i;
		}
	}
	for(int k=1;k<=m;k++){
		if((k-1)*(n/m)+1<=y&&k*(n/m)>=y){
			cout<<k;
		}
	}
	return 0;
}