#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<queue>
#define maxn 1000010
using namespace std;
int n,k,ans,i,j,t;
int a[maxn];
int suan(int x,int y)
{
    int min=1073741824,lon=0;
	for(i=0;i<=x-k;i++)
	  {
	  	for(j=i;j<i+y;j++)
	  	  {
	  	  	for(t=j+1;t<i+y;t++)
	  	  	  {
	  	  	  	lon+=abs(a[t]-a[j]);
	  	  	  }
	  	  }
	  	if(lon<min)
	  	  min=lon;
	  }
	return min;
}
int main()
{
	freopen("qwa.in","r",stdin);
	freopen("qwa.out","w",stdout);
	cin>>n>>k;
	for(i=0;i<n;i++)
	  {
	  	cin>>a[i];
	  }
	cout<<suan(n,k);
	fclose(stdin);fclose(stdout);
	return 0;
}