import java.io.*;
import java.util.*;

/**
 * @author ajay subramanya
 * */
public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        for(int i = 0; i <= n; i++){
            String line = in.nextLine();
            if (line.isEmpty() || line == null) continue;
            char[] letters = line.toCharArray();
            int len = letters.length - 1;
            int changes = 0;
            for(int j = 0; j <= len / 2 ; j++){
                if (letters[j] != letters[len - j])
                    changes += Math.abs(Character.toLowerCase(letters[j]) - Character.toLowerCase(letters[len - j]));
            }
            System.out.println(changes);
        }
    }
}