#include <stdio.h>
    #include <stdlib.h>
     
    int main(int argc, char *argv[])
    {
    freopen("mark.in","r",stdin);
    freopen("mark.out","w",stdout);
      int n,m,x,A[1000],i,j,t,a,b,c;
      scanf("%d%d",&n,&m);
      for(i=1;i<=n;i++)
      scanf("%d",&A[i]);
      scanf("%d",&x);
      a=A[x];
      for(j=1;j<=n;j++)
         for(i=1;i<=n-j;i++)
      if(A[i]<A[i+1]) {t=A[i+1];A[i+1]=A[i];A[i]=t;}
      for(i=1;1<=n;i++)
      if(A[i]==a)  break;
      for(b=1;b<=n;b++)
       if(i-b*(n/m)<=0)  break;
          c=b;
       printf("%d",c);   	
      return 0;
    }