#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define repi(i, a, b) for (int i = (a); i < (b); i++)
#define all(a) (a).begin(), (a).end()

using namespace std;
using i32 = int;
using i64 = long long;
using f64 = double;
using vi32 = vector<i32>;
using vvi32 = vector<vi32>;
using vi64 = vector<i64>;
using vvi64 = vector<vi64>;

template<typename T> inline bool amin(T &x, T y) { if (y < x) { x = y; return true; } return false; }
template<typename T> inline bool amax(T &x, T y) { if (x < y) { x = y; return true; } return false; }

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, k;
  cin >> n >> k;
  vi64 a(n);
  rep(i, n) cin >> a[i];
  i64 ans = 1e18;
  rep(i, n - k + 1) {
    vi64 v(k);
    rep(j, k) v[j] = a[j + i];
    sort(all(v));
    i64 c = v[k / 2];
    i64 sum = 0;
    rep(j, k) sum += abs(v[j] - c);
    amin(ans, sum);
  }
  cout << ans << endl;
  return 0;
}