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.

Hint: always remember to first eliminate all spaces after the last word!

Length of last word

01 public int lengthOfLastWord(String s) {
02     char []str=s.toCharArray();
03     if(str.length==0)
04         return 0;
05     int count=0;
06     int last=str.length-1;
07   
08     //eliminate all space at the end
09     while(last>=0 && str[last]==' ')
10     {
11         last--;
12     }
13   
14     while(last>=0 && str[last]!=' ')
15     {
16         count++;
17         last--;
18     }
19   
20     return count;
21 }