using System;
using System.IO;
using System.Linq;
using System.Text;
using System.Collections.Generic;
using System.Diagnostics;
using System.Numerics;
using Enu = System.Linq.Enumerable;

class Program
{
    public void Solve()
    {
        int N = Reader.Int(), K = Reader.Int();
        var A = Reader.IntArray(N);
        var B = Reader.IntArray(N);
        long ans = 0, diff = Diff(0, A, B);
        for (int t = 0; t < K; t++)
        {
            ans += diff;
            diff += NextPermutation(A, B);
        }
        Console.WriteLine(ans);
    }

    long NextPermutation(int[] A, int[] B)
    {
        int N = A.Length, L = 0, R = N - 1;
        for (L = N - 2; L >= 0; L--)
            if (A[L] < A[L + 1])
            {
                while (A[L] >= A[R]) R--;
                break;
            }
        long res = -Diff(Math.Max(0, L), A, B);
        if (L >= 0) Swap(ref A[L], ref A[R]);
        Array.Reverse(A, L + 1, N - L - 1);
        res += Diff(Math.Max(0, L), A, B);
        return res;
    }

    static void Swap<T>(ref T a, ref T b) { T t = a; a = b; b = t; }

    long Diff(int L, int[] A, int[] B)
    {
        long res = 0;
        for (int i = L; i < A.Length; i++)
            res += Math.Abs(A[i] - B[i]);
        return res;
    }
}


class Entry { static void Main() { new Program().Solve(); } }
class Reader
{
    private static TextReader reader = Console.In;
    private static readonly char[] separator = { ' ' };
    private static readonly StringSplitOptions op = StringSplitOptions.RemoveEmptyEntries;
    private static string[] A = new string[0];
    private static int i;
    private static void Init() { A = new string[0]; }
    public static void Set(TextReader r) { reader = r; Init(); }
    public static void Set(string file) { reader = new StreamReader(file); Init(); }
    public static bool HasNext() { return CheckNext(); }
    public static string String() { return Next(); }
    public static int Int() { return int.Parse(Next()); }
    public static long Long() { return long.Parse(Next()); }
    public static double Double() { return double.Parse(Next()); }
    public static int[] IntLine() { return Array.ConvertAll(Split(Line()), int.Parse); }
    public static int[] IntArray(int N) { return Enu.Range(0, N).Select(i => Int()).ToArray(); }
    public static int[][] IntTable(int H) { return Enu.Range(0, H).Select(i => IntLine()).ToArray(); }
    public static string[] StringArray(int N) { return Enu.Range(0, N).Select(i => Next()).ToArray(); }
    public static string Line() { return reader.ReadLine().Trim(); }
    private static string[] Split(string s) { return s.Split(separator, op); }
    private static string Next() { CheckNext(); return A[i++]; }
    private static bool CheckNext()
    {
        if (i < A.Length) return true;
        string line = reader.ReadLine();
        if (line == null) return false;
        if (line == "") return CheckNext();
        A = Split(line);
        i = 0;
        return true;
    }
}