using System;
using System.Collections.Generic;
using System.Collections;
using System.Collections.Specialized;
using System.Linq;
using System.Text;
using System.IO;
using System.Reflection;
using static System.Math;
using System.Numerics;
using System.Threading;
using System.Runtime.CompilerServices;
using System.Diagnostics;
//using nint=System.Int32;
static class Program{
	const int mod=(int)1e9+7;
	static void Main(){
		Sc sc=new Sc();
		var s=sc.Ia;
		var a=sc.Ia;
		var b=Enumerable.Repeat(-1,s[0]).ToArray();
		for(int i = 0;i < s[1];i++) {b[i]=1;}
		if(s[1]==0){
			Console.WriteLine(Min(Fu(a[0]),Fu(a[s[0]-1])));
			return;
		}
		long Fu(int x) {
			var h=new int[s[0]];
			long p=0;
			for(int i = 0;i < s[0];i++) {h[i]=Abs(x-a[i]);}
			Array.Sort(h);
			for(int i = 0;i < s[0];i++) {p+=h[i]*b[i];}
			return p;
		}
		Bit bit=new Bit(s[0]);
		long ans=long.MaxValue>>1;
		for(int i = 0;i < s[0];i++) {bit.Ud(i,a[i]);}
		for(int i = 0,j=-1,k=s[1];i < s[0];i++) {
			while(k!=s[0]&&Abs(a[i]-a[j+1])>Abs(a[i]-a[k])){j++;k++;}
			long p=0;
			if(j!=-1){p+=bit.Get2(0,j)-(j+1L)*a[i];}
			if(k!=s[0]){p+=((long)s[0]-k)*a[i]-bit.Get2(k,s[0]-1);}
			if(j<i){p-=bit.Get2(j+1,i)-((long)i-j)*a[i];}
			if(i<k){p-=((long)k-i)*a[i]-bit.Get2(i,k-1);}
			ans=Min(ans,p);
		}
		Console.WriteLine(ans);
	}
}
public class Bit{
	private int n;
	private long[] bit;
	public Bit(int n){
		this.n=n;
		bit=new long[n+1];
	}
	public void Ud(int a,long p){a++;while(a<=n){bit[a]+=p;a+=a&-a;}}
	public long Get(int n){
		n++;
		long a=0;
		while(n>0){a+=bit[n];n-=n&-n;}
		return a;
	}
	public long Get2(int m,int n){
		long a=0,b=0;
		n++;
		while(n>m){a+=bit[n];n-=n&-n;}
		if(n==m){return a;}
		while(n!=m){b+=bit[m];m-=m&-m;}
		return a-b;
	}
	public void Clear(){bit=new long[n+1];}
}
public class Sc{
	public int I{get{return int.Parse(Console.ReadLine());}}
	public long L{get{return long.Parse(Console.ReadLine());}}
	public double D{get{return double.Parse(Console.ReadLine());}}
	public string S{get{return Console.ReadLine();}}
	public int[] Ia{get{return Array.ConvertAll(Console.ReadLine().Split(),int.Parse);}}
	public long[] La{get{return Array.ConvertAll(Console.ReadLine().Split(),long.Parse);}}
	public double[] Da{get{return Array.ConvertAll(Console.ReadLine().Split(),double.Parse);}}
	public string[] Sa{get{return Console.ReadLine().Split();}}
	public object[] Oa{get{return Console.ReadLine().Split();}}
	public int[] Ia2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),int.Parse);}}
	public int[] Ia3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),int.Parse);}
	public int[] Ia3(int a){return Array.ConvertAll((Console.ReadLine()+" "+a.ToString()).Split(),int.Parse);}
	public long[] La2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),long.Parse);}}
	public long[] La3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),long.Parse);}
	public long[] La3(int a){return Array.ConvertAll((Console.ReadLine()+" "+a.ToString()).Split(),long.Parse);}
	public double[] Da2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),double.Parse);}}
	public double[] Da3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),double.Parse);}
	public T[] Arr<T>(int n,Func<T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f();}return a;}
	public T[] Arr<T>(int n,Func<int,T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(i);}return a;}
	public T[] Arr<T>(int n,Func<string[],T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(Console.ReadLine().Split());}return a;}
	public T[] Arr<T>(int n,Func<int,string[],T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(i,Console.ReadLine().Split());}return a;}
	public (T,T) Tp2<T>(){var s=Console.ReadLine().Split();return (Ct<T>(s[0]),Ct<T>(s[1]));}
	public (T,T,T) Tp3<T>(){var s=Console.ReadLine().Split();return (Ct<T>(s[0]),Ct<T>(s[1]),Ct<T>(s[2]));}
	public (T1,T1,T2) Tp3<T1,T2>(){var s=Console.ReadLine().Split();return (Ct<T1>(s[0]),Ct<T1>(s[1]),Ct<T2>(s[2]));}
	private T Ct<T>(string s){return (T)Convert.ChangeType(s,typeof(T));}
}