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.

从后往前计算，先要除去后面的空格，遇到第一个不是空格开始计算，遇到空格停止。

class Solution {public:    int lengthOfLastWord(string s) {        int l=s.size(),count=0;               while(s[l-1]==' ')l--;        for(int i=l-1;i>=0;i--){            if(s[i]!=' ')            count++;            else break;        }        return count;    }};