LengthofLastWord.java

/**
 * Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return
 * the length of last word in the string.
 *
 * <p>If the last word does not exist, return 0.
 *
 * <p>Note: A word is defined as a character sequence consists of non-space characters only.
 *
 * <p>For example, Given s = "Hello World", return 5.
 */
public class LengthofLastWord {
 public int lengthOfLastWord(String s) {
 int i = s.length() - 1;
 while (i >= 0 && s.charAt(i) == ' ') {
 i--;
 }
 if (i < 0) return 0;
 int j = i;
 while (j - 1 >= 0 && s.charAt(j - 1) != ' ') {
 j--;
 }
 return i - j + 1;
 }
}