class Solution {
    public boolean detectCapitalUse(String word) {
        if(word.equals(word.toUpperCase())) return true;
        if(word.equals(word.toLowerCase())) return true;
        if(Character.isUpperCase(word.charAt(0)) && 
               word.substring(1).equals(word.substring(1).toLowerCase())) return true;
        
        return false;
    }
}