#include<iostream>
#include<vector>
#include<algorithm>
#include<map>
using  namespace std;

int n;


int main() {
	cin >> n;
	vector<int>arr(n,0);
	for (int i = 0; i < n; ++i) {
		cin >> arr[i];
	}
	sort(arr.begin(), arr.end());
	long long x =0, y=0;
	int l, r;
	for ( l = 0, r = n - 1; l < r; l++, r--) {
		x += arr[r];
		y += -arr[l];
	}
	if (l == r) x += arr[r];
	cout << x - y << endl;
	return 0;
	
}