#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <map>
using namespace std;
typedef long long ll;
#define rep(i, n) for (int i=0;i < (int)(n);i++)

int main(){
  int n,k;
  cin >> n >> k;
  ll ans = 1LL << 60;
  vector<ll> v(n);
  ll res = 0;
  for (int i = 0; i < n;i++){
    cin >> v[i];
  }
  int cnt = 0;
  for (int i = 0; i < n;i++){
    if (i < k) res += abs(v[i]-v[0]);

    else res -= abs(v[i]-v[0]);
  }
  ans = min(ans,res);
  res = 0;
  cnt = 0;
  for (int i = n-1; i >= 0;i--){
    if (n-1-i < k) res += abs(v[i]-v[n-1]);
    else res -= abs(v[i]-v[n-1]);
  }
  ans = min(ans,res);
  cout << ans << endl;
}