LeetCode Length of Last Word

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

.

Solution:

class Solution {
public:
int lengthOfLastWord(const char *s) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
const char*p1=s,*p2=s;
int last=0;
do{
p1=p2;
while(*p1==' ')
++p1;
if(*p1=='\0')
break;
p2=p1;
while(*p2!=' '&&*p2!='\0')
++p2;
last=p2-p1;
}while(*p2);

return last;
}
};