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
 



這道題簡直太簡單，面試都考這樣的就好了，需要求最後一個單詞的長度，如果不存在最後返回0。而且s只存在字母和空格，不存在其他的字符，只需要從後向前遍歷數字符就可以了，代碼如下：

 1 class Solution {
 2 public:
 3     int lengthOfLastWord(string s) 
 4     {
 5         int len = 0, tail = s.length() - 1;
 6         while (tail >=0 && s[tail] == ‘ ‘)
 7             tail--;
 8         while
 
 (tail >=0 && s[tail] != ‘ ‘)
 9         {
10             tail--;
11             len++;
12         }
13         return len;
14     }
15 };

LeetCode 58. Length of Last Word