ARTS leetcode6 Length of Last Word

谁借莪１个温暖的怀抱￠ 2022-04-24 12:10 113阅读 0赞

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.
    
    Example:
    
    Input: "Hello World"
    Output: 5

题目意思：求最后一个单词的长度，如果最后一个单词不存在，返回0.

思路：那就从从字符串最后一个字符开始循环，直到遇到第一个’ '，然后用字符串的长度减掉此时的索引，再减掉1就行。

代码实现：

class Solution {
        public int lengthOfLastWord(String s) {
         if(s!=null && s.length()>0){
             s = s.trim();
             for(int i=s.length()-1;i>=0;i--){
                 if(s.charAt(i) == ' '){
                     return s.length()-i-1;
                 }
             }
              return s.length();
         }
        
            return 0;
        }
    }

Runtime: 0 ms, faster than 100.00% of Java online submissions for Length of Last Word.
    Memory Usage: 37.3 MB, less than 18.99% of Java online submissions for Length of Last Word.
    Next challeng

下面在看看leetcode上别的大佬的优质解法：

return s.trim().length()-s.trim().lastIndexOf(" ")-1;

Runtime: 0 ms, faster than 100.00% of Java online submissions for Length of Last Word.
    Memory Usage: 37.1 MB, less than 21.05% of Java online submissions for Length of Last Word.

大佬真的是一行代码解决问题。

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTI5MzQzMjU_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTI5MzQzMjU_size_16_color_FFFFFF_t_70]: /images/20220215/a587077a79c1405dbe51a06360098110.png