How can you check if a character is a letter using the `Character` class in Java?
You can check with `if(c >= 'A' && c <= 'Z') { // check for letter }`.
You're on the right track, but comparing the character with 'A' and 'Z' doesn't account for lowercase letters.
Can you try using `Character.isLetter(c)` instead to check for both uppercase and lowercase letters?