class Solution {
    public int lengthOfLastWord(String s) {
       int i = s.length() - 1, length = 0;
       while (s.charAt(i) == ' ') {
           i -= 1;
       }
       while (i >= 0 && s.charAt(i) != ' ') {
           length += 1;
           i -= 1;
       } 
       return length;
    }
}