LeetCode OJ：Length of Last Word（最后一个词的长度）

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.

求最后一个非空单词的长度而已，没什么注意点，直接看代码，理解题目意思就可以了：

class Solution {
public:
    int lengthOfLastWord(string s) {
        int len  = s.length();
        if(len == 0) return 0;
        while(s[len - 1] == ' ')
            if(len - 1 >= 0)
                len--;
            else
                return 0;
        len--;
        int lenCount = 0;
        while(s[len] != ' ' && len >= 0){
            lenCount++, len--;
        }
        return lenCount;
    }
};

 java版本的代码如下所示，倒过来读很容易了：

public class Solution {
    public int lengthOfLastWord(String s) {
        int i = s.length() - 1;
        while(i >= 0 && s.charAt(i) == ' ')
            i--;
        int end = i+1;
        while(i >= 0 && s.charAt(i) != ' ')
            i--;
        int start = i+1;
        return end - start;
    }
}