fn is_rotation(s1: &str, s2: &str) -> bool {
s1.len() == s2.len() && (s1.to_owned() + s1).contains(s2)
}
fn main() {
let s1 = "abbc";
let s2 = "cabb";
println!("{}", if is_rotation(s1, s2) { "yes" } else { "no" });
let s1 = "abbc";
let s2 = "bbac";
println!("{}", if is_rotation(s1, s2) { "yes" } else { "no" });
}
/*
run:
yes
no
*/