#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++)
#define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++)
#define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--)
#define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())
#define len(x) ((ll)(x).length())

template<class T>
struct Median {
private:
    priority_queue<T> left;
    priority_queue<T, vector<T>, greater<T>> right;
    T min_value = numeric_limits<T>::min();
    T max_value = numeric_limits<T>::max();
    
public:
    Median() {
        left.push(min_value);
        right.push(max_value);
    }
    
    void push(T value) {
        T values[3];
        values[0] = left.top(); left.pop();
        values[1] = value;
        values[2] = right.top(); right.pop();
        sort(values, values + 3);
        left.push(values[0]);
        right.push(values[2]);
        if (left.size() == right.size()) {
            left.push(values[1]);
        }
        else {
            right.push(values[1]);
        }
    }
    
    pair<T, T> get() {
        pair<T, T> result;
        if (left.size() != right.size()) {
            result.first = result.second = left.top();
        }
        else {
            result.first = left.top();
            result.second = right.top();
        }
        return result;
    }
};

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    ll n;
    cin >> n;
    vector<ll> a(n);
    rep(i, n) cin >> a[i];
    Median<ll> m;
    rep(i, n) m.push(a[i]);
    auto me = m.get();
    ll ans = 0;
    rep(i, n) {
        ans += abs(me.first - a[i]);
    }
    cout << ans << endl;
    return 0;
}