LeetCode 58 _ Length Of Last Word 最后一个单词的长度 (Easy)

Description:

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

 

 

Solution:

这道题的要求是输出字符串中最后一个单词的长度

 

这题比较简单，既然是要得到最后一个单词的长度，那么我们只需要从最后遍历，首先删除末尾的所有空characters，然后不停向前搜索，不是空串那么将计数加一，直到搜索到空串或者搜索到第0位。

 

 

Code:

 public int lengthOfLastWord(String s) {
        int n = s.length()-1;
        
        while (n >= 0 && s.charAt(n)==' '){
        	n--;
        }
        int res = 0;
        while (n >= 0 && s.charAt(n)!=' '){
        	n--;
        	res++;
        }
        return res;
    }

　　

 

提交情况:

Runtime: 0 ms, faster than 100.00% of Java online submissions for Length of Last Word.
Memory Usage: 37.2 MB, less than 19.91% of Java online submissions for Length of Last Word.