#include <bits/stdc++.h>

using namespace std;
#define endl "\n"
#define int long long
typedef long long ll;
void solved() {
  int n;
  cin >> n;
  int a[n + 1];
  for (int i = 1; i <= n; i++) cin >> a[i];
  sort(a + 1, a + n + 1);
  int sum1 = 0, sum2 = 0;
  for (int i = 1, j = n; i < j; i++, j--) {
    sum1 += a[j];
    sum2 -= a[i];
  }
  if (n & 1) sum1 += a[(n + 1) / 2];
  cout << sum1 - sum2 << endl;
}
signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  /* int t = 1;
   cin >> t;
   while (t--)*/
  solved();

  return 0;
}