Leetcode Length of Last Word

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

.

解题思路：

方法一：

这道题主要是考虑一下最后是不是空格，方法是倒着找不是空格的字符并计数。这个速度最快。

方法二：

用split函数把字符串按照空格分隔好，返回最后那个就行。这个比较慢。

Java code:

Method1:

public int lengthOfLastWord(String s) {
if(s == null || s.length() < 1) {
return 0;
}
s = s.trim();
if(s.length()==0) {
return 0;
}
int result = 0;

for(int i=s.length()-1; i>=0; i--) {
if(s.charAt(i) != ' ') {
result +=1;
}else {
break;
}
}
return result;
}

Method2: use split

public int lengthOfLastWord(String s) {
if(s==null || s.length() < 1) {
return 0;
}
String[] temp = s.split(" ");
if(temp.length == 0) {
return 0;
}
return temp[temp.length-1].length();
}

Reference:

1. http://www.cnblogs.com/springfor/p/3872326.html