【LeetCode】58 - 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.

 class Solution {
 public:
     int lengthOfLastWord(string s) {
         int n=s.size()-;
         while(n>=&&s.at(n)&&s.at(n)==' ')n--;
         int i=;

         for(;n>=&&s.at(n)&&s.at(n)!=' ';n--,i++);
         return i;
     }
 };