#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define rep3(i, l, n) for (int i = l; i < n; ++i)
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define out(a) cout << a << endl
#define SZ(v) (int)v.size()
#define inf (int)(1e9+7)

int n;
int a[100001];
ll calc(int key) {
    int med;
    med = a[key];
    ll sum = 0;
    rep(i, n) {
        sum += abs(a[i] - med);
    }
    return sum;
}
int main() {
    
    cin >> n;
    
    
    rep(i, n) {
        cin >> a[i];
        
    }
    sort(a, a + n);
    
    if (n % 2 == 0) {
        out(min(calc(n / 2 - 1), calc(n / 2)));
    } else {
        
        out(calc(n / 2));
    }
    
}