#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
#define rep(i,a) for(int i=0;i<(a);i++)
#define MOD 1000000007

int N;
const ll MA=1000000000;
ll a[100000];

ll solve(ll x){
  ll res=0;
  rep(i,N) res+=abs(a[i]-x);
  return res;
}

int main(){
  cin>>N;
  rep(i,N) cin>>a[i];
  sort(a,a+N);
  int lb=-MA,ub=MA;
  while(ub-lb>1){
    ll mid=(lb+ub)/2;
    if(solve(mid)>solve(mid+1)) lb=mid;
    else ub=mid;
  }
  cout<<solve(lb)-1<<endl;
  return 0;
}