struct Solution;
impl Solution {
fn reverse_words(s: String) -> String {
s.split_whitespace().rev().collect::<Vec<&str>>().join(" ")
}
}
#[test]
fn test() {
let s: String = "the sky is blue".to_string();
let res: String = "blue is sky the".to_string();
assert_eq!(Solution::reverse_words(s), res);
}