leetcode: 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(const char *s) {                int ret = 0;                char *pCur = (char *)s;        char *pBase;                while (*pCur != '\0')        {            pCur++;        }                pCur--;        while (pCur >= s)        {            while (pCur >= s && *pCur == ' ')                pCur--;                            if (pCur < s)                break;                            pBase = pCur;                        while (pCur >=s && *pCur != ' ')                pCur--;                            return pBase-pCur;        }                return 0;    }};