## [leetcode.com]算法题目 - 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.

 1 class Solution {
2 public:
3     int lengthOfLastWord(const char *s) {
4         // Start typing your C/C++ solution below
5         // DO NOT write int main() function
6         int len = strlen(s);
7         if(0==len) return 0;
8
9         int last = len;
10         int first = 0;
11         while(last>0 && s[last-1]==' '){
12             last--;
13         }
14         while(first<last && s[first]==' '){
15             first++;
16         }
17         if(0==last) return 0;
18
19         int i;
20         for(i=last-1;i>=first;i--){
21             if(s[i]==' ')  break;
22         }
23         return (last-i-1);
24     }
25 };

posted on 2013-09-25 22:48  Horstxu  阅读(326)  评论(0编辑  收藏  举报