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.

我的解法：

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public class  {
    public int lengthOfLastWord(String s) {
        if (s.trim().length() == 0) {
            return 0;
        }
        String[] strs = s.split(" ");
        return strs[strs.length-1].length();
    }
}

思想：为0的case判断，不为0则split开后取最后一个元素拿长度即可，题目简单，主要是0的判断。

一行解法：

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public class  {
    public int lengthOfLastWord(String s) {
        return s.trim().length()-s.trim().lastIndexOf(" ")-1;
    }
}

思想：字符串长度减去最后一个空格的位置再减1。