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 len = strlen(s), cnt = 0;        bool flag = false;        for(int i = len-1; i >= 0 ; --i){            if(s[i]!=‘ ‘) {flag =true;cnt++;}            else if(flag) break;        }        return cnt;    }};