Reverse the String

Given a string A.

Return the string A after reversing the string word by word.

NOTE:

1. A sequence of non-space characters constitutes a word.

2. Your reversed string should not contain leading or trailing spaces, even if it is present in the input string.

3. If there are multiple spaces between words, reduce them to a single space in the reversed string.

Input Format

The only argument given is string A.

Output Format

Return the string A after reversing the string word by word.

For Example

Input 1:
    A = "the sky is blue"
Output 1:
    "blue is sky the"

Input 2:
    A = "this is ib"
Output 2:
    "ib is this"

class Solution {
    public String reverseWords(String s) {
        String[] list = s.split(" ");
        StringBuilder str = new StringBuilder();
        boolean first = true;
        for (int i = list.length - 1; i >= 0; i--) {
            if (list[i].length() != 0) {
                if (first) {
                    str.append(list[i]);
                    first = false;
                } else
                    str.append(" " + list[i]);
            }
        }
        return str.toString();
    }
}