leetcode No58. Length of Last Word

Question：

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.

求最后一个单词的长度

Algorithm：

从后往前扫，要注意最后一个字符如果是 ' ' 要跳过。

Accepted Code：

class Solution {public:    int lengthOfLastWord(string s) {        if(s.size()==0)return 0;        int N=s.size();        int count=0;        for(int i=N-1;i>=0;i--)        {            if(s[i]==' ')            {                if(count>0)        //避免最后一个字符是空的                    return count;            }            else                ++count;        }        return count;    }};