LeetCode 058 Length of Last Word

题目

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

.

思路

1 大体逻辑很简单，就是从最后往前计数，碰到空格停止。

2 要考虑边角情况：最两边出现空格。全篇没有空格，全篇都是空格。

代码

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