[Leetcode]Length of Last Word

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.

For example, 
Given s = "Hello World",

return 5.

返回字符串里最后一个单词的长度~可以直接用python里的split()函数，代码如下~

class Solution:    # @param s, a string    # @return an integer    def lengthOfLastWord(self, s):        if s is None: return 0        s_split = s.split()        return 0 if len(s_split) == 0 else len(s_split[-1])

还可以运用简单的字符串操作，先去掉尾部的空格，然后读到下一个空格，记录下长度

class Solution:    # @param s, a string    # @return an integer    def lengthOfLastWord(self, s):        if s is None or len(s) == 0: return 0        end = len(s) - 1        while end >= 0 and s[end] == ' ': end -= 1        start = end        while start >= 0 and s[start] != ' ': start -= 1        return end - start