#include<iostream>
#include<algorithm>
using namespace std;
using ll = long long; 

int main(){
  ll n;
  cin >> n;
  ll a[100000];
  for(int i=0;i<n;i++)cin >> a[i];
  sort(a,a+n);
  ll x=a[n/2];
  ll y=a[(n+1)/2];
  ll sumx=0,sumy=0;
  for(int i=0;i<n;i++){
      sumx+=abs(a[i]-x);
      sumy+=abs(a[i]-y);
  }
  cout << min(sumx,sumy) << endl;
}