[LeetCode刷题记录]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.

思路：指针扫描一次，遇到空格置零。要特别注意多个空格的情况。要判断空格后面是否为空格，或者是指到字符串尾部。

对char *操作时注意一些细节问题。

class Solution {public:    int lengthOfLastWord(const char *s) {        if(s==NULL)            return 0;        int ret=0;        int flag=0;        while(*s){            if(*s!=' ')                ++ret;            if(*s==' '&&*(s+1)&&*(s+1)!=' ')                ret=0;                ++s;        }        return ret;    }};