public static int theLoveLetterMystery(String s) {
        //goal: find min operations req to convert string s into a palindrome
        //o(n) time, o(1) space
        if(s.length() == 1) return 0; //len of 1 is always palindromic
        
        int minOperations = 0;
        int left = 0, right = s.length() - 1;
        //use a left pointer at the start and a right pointer at the end to process both ends of str
        while(left < right){
            char leftChar = s.charAt(left);
            char rightChar = s.charAt(right);
            //if char at left is < right, reduce right
            if(leftChar < rightChar){
                minOperations += rightChar - leftChar;
            }
            //if char at left is > right, reduce left
            else if(leftChar > rightChar){
                minOperations += leftChar - rightChar;
            }
            left++;
            right--;            
        }
        return minOperations;
    }