#include<bits/stdc++.h>
    using namespace std;
    const int maxn=10005;
    int a[maxn];
    bool cmp(const int q,const int w){return q>w;}
    int main(){
    	freopen("mark.in","r",stdin);
    	freopen("mark.out","w",stdout);
    	int m,n,x;
    	cin>>n>>m;
    	for(int i=1;i<=n;i++)cin>>a[i];
		cin>>x;
		int qwq=a[x],cq;
    	sort(a+1,a+1+n,cmp);
    	for(int i=n;i>=1;i--)
    	if(a[i]==qwq)cq=i;
    	int q=n/m;
    	if(cq%q==0)cout<<cq/q;
    	else
    	cout<<cq/q+1;
    	 
    	return 0;
    }
    /*
    10 3
1
1
1
10000
1
1
1
1
1
1
*/