/* -*- coding: utf-8 -*-
 *
 * 1391.cc:  No.1391 ±1 Abs Sum - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 200000;
const long long LINF = 1LL << 62;

/* typedef */

typedef long long ll;

/* global variables */

int as[MAX_N];

/* subroutines */

ll f(int n, int k, int x) {
  ll sum = 0;
  int r = n - k;
  for (int i = 0, j = n - 1; i <= j;) {
    int di = abs(x - as[i]), dj = abs(x - as[j]);
    if (di >= dj) {
      if (r > 0) sum -= di, r--;
      else sum += di;
      i++;
    }
    else {
      if (r > 0) sum -= dj, r--;
      else sum += dj;
      j--;
    }
  }
  return sum;
}

/* main */

int main() {
  int n, k;
  scanf("%d%d", &n, &k);
  for (int i = 0; i < n; i++) scanf("%d", as + i);

  ll f0 = f(n, k, as[0]);
  ll f1 = f(n, k, as[n - 1]);
  printf("%lld\n", min(f0, f1));
  return 0;
}