import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;

public class Main{
    public static void main(String[] args) throws IOException {
        BufferedReader r=new BufferedReader(new InputStreamReader(System.in));
        String s[]=r.readLine().split(" ");
        int n=Integer.parseInt(s[0]);
        String line[]=r.readLine().split(" ");
        int[] arr=new int[n];
        for (int i = 0; i < n; i++) {
            arr[i]=Integer.parseInt(line[i]);
        }
        int res=0;
        Arrays.sort(arr);
        //偶数下 算对称距离
        if(n%2==0){
            for (int i = 0; i <n/2 ; i++) {
                res+=arr[n-i-1]-arr[i];
            }
            System.out.println(res);
        }
        //奇数下 也算 但是除去中位数
        else{
            for (int i = 0; i <n/2 ; i++) {
                res+=arr[n-i-1]-arr[i];
            }
            System.out.println(res);
        }
    }
}