#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cmath>
#include<iomanip>
using namespace std;
class STUDENT{
public:
	int num;//编号
	int mark;//分数
	int grade;//第几名
}a[1000];
int n,m;
void input(void){
	scanf("%d%d",&n,&m);
	for(int i=0;i<n;i++){
		a[i].num=i+1;
		scanf("%d",&a[i].mark);
		a[i].grade=0;
	}
}
bool cmp(STUDENT a,STUDENT b){
	return a.mark>b.mark;
}
void divide(void){
	sort(a,a+n,cmp);
	int i;
	a[0].grade=1;
	for(i=1;i<n;i++){
		a[i].grade=a[i-1].grade+1;
	}
}
void output(int x){
	double temp=(double)n/(double)m;
	int p;
	for(int i=0;i<n;i++){
		if(a[i].num==x){
			p=i;
			break;
		}
	}
	double gn=(double)a[p].grade;
	double ans=gn/temp;
	cout<<ceil(ans)<<endl;
}
int main(){
	freopen("mark.in","r",stdin);
	freopen("mark.out","w",stdout);
	input();
	divide();
	int x;
	scanf("%d",&x);
	output(x);
	return 0;
}