//https://ncode.syosetu.com/n4830bu/270/
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    int N, K;
    cin >> N >> K;
    vector<int> p(N);
    vector<ll> B(N);
    for (int i = 0; i < N; i++) {
        cin >> p[i];
    }
    for (int i = 0; i < N; i++) {
        cin >> B[i];
    }
    ll maine = 0, ans = 0;
    for (int i = 0; i < N; i++) {
        maine += abs(p[i] - B[i]);
    }
    auto prev = p;
    while (K--) {
        ans += maine;
        if (!next_permutation(p.begin(), p.end()))
            iota(p.begin(), p.end(), 1);
        for (int i = N - 1; i >= 0; i--) {
            if (i < N - 1 && prev[i] == p[i] && prev[i + 1] == p[i + 1])
                break;
            maine -= abs(prev[i] - B[i]);
            maine += abs(p[i] - B[i]);
        }

        if (!next_permutation(prev.begin(), prev.end()))
            iota(prev.begin(), prev.end(), 1);
    }
    cout << ans << endl;
}