Leetcode Length of Last Word (java)

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 1:

public class Solution {    public int lengthOfLastWord(String s) {        if(s == null || s.length() ==0)     return 0;     int result = 0;     int length = s.length();     boolean flag = false;     for(int i=length-1; i>=0; i--)     {     char c = s.charAt(i);     if((c>='A' && c<='Z') ||( c>='a' && c<='z'))     {     flag = true;     result++;     }else     {     if(flag)     {     return result;     }     }     }     return result;      }}

soulution 2:

public class Solution {    public int lengthOfLastWord(String s) {       if(s == null || s.length() ==0 || s.trim().equals(""))     return 0;    String[] strs = s.split(" ");        String str = strs[strs.length-1];     return str.length();    }}