LeetCode（58）——Length of Last Word

题目：

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.

If the last word does not exist, return 0.

Note: A word is defined as a character sequence consists of non-space characters only.

Example:

Input: "Hello World"
Output: 5

AC：

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