#include<cstdio>
#include<iostream>
#include<algorithm> 
#include<cmath>
const int maxn=10010;
using namespace std;
typedef long long ll;
ll s[maxn];
int a[maxn];
int main()
{
	freopen("qwa.in","r",stdin);
	freopen("qwa.out","w",stdout);
	int n,k;
	ll d,ans=23333333333;
	scanf("%d%d",&n,&k);
	for(int i=1;i<=n;i++)
		scanf("%d",&a[i]);
	sort(a+1,a+1+n);
	s[1]=0;
	for(int i=2;i<=n;i++)
		s[i]=s[i-1]+abs((i-1)*(a[i]-a[i-1]));
	for(int i=1;i<=n-k+1;i++)
	{
		d=0;
		for(int j=i;j<i+k;j++)
			d+=(s[j]-s[i]-abs((i-1)*(a[j]-a[i])));
		ans=min(ans,d);
	}
	printf("%d",ans);
	return 0;
 }