#include<bits/stdc++.h>
using namespace std;
#define int long long
#define boost ios::sync_with_stdio(0);cin.tie(0)
 
int n, m, x;
vector<int> lengths;

int f(int x) {
    int cost = 0;
    for(int l: lengths) 
    cost += abs(x-l);
    return cost;
}

int ternary_search_minima(int l, int r) {
    while(r-l > 3) {
        int m1 = l + (r-l)/3;
        int m2 = r - (r-l)/3;
        if(f(m1) < f(m2)) r = m2;
        else l = m1;
    }
    int minima = __LONG_LONG_MAX__;
    for(int i = l; i <=r ; i++) {
        minima = min(minima, f(i));
    }
    return minima;
}
 
void purple()
{   
    cin >> n;
    for(int i = 0; i < n; i++) {
        cin >>x;
        lengths.push_back(x);
    }
    cout << ternary_search_minima(0, 10000000000000);
}
 

signed main() {
    boost;
    int t=1;
    while(t--) purple();
}