leetcode 58. Length of Last Word

Seawolf

1. Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.
   
2. 
   
3. If the last word does not exist, return 0.
   
4. 
   
5. Note: A word is defined as a character sequence consists of non-space characters only.
   
6. 
   
7. Example:
   
8. 
   
9. Input: "Hello World"
   
10. Output: 5

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1. class Solution {
   
2.     public int lengthOfLastWord(String s) {
   
3.         
   
4.         s = s.replaceAll(" +"," ");
   
5.         
   
6.         if(s.equals(" ")){
   
7.             
   
8.             return 0;
   
9.         }
   
10.         
    
11.         String[] result = s.split(" ");
    
12.         
    
13.         return result[result.length-1].length();
    
14.         
    
15.     }
    
16. }

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利用split方法，效率有点低，继续改进。

1. class Solution {
   
2.     public int lengthOfLastWord(String s) {
   
3.         
   
4.         s = s.trim();
   
5.         
   
6.         return s.length() - (s.lastIndexOf(" ") +1) ;
   
7.     }
   
8. }
   

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