fn main() {
    let s: Vec<char> = {
        let mut buf = String::new();
        std::io::stdin().read_line(&mut buf).unwrap();
        buf.trim_end().chars().collect()
    };

    for i in 0..26 {
        let c = ('a' as u8 + i as u8) as char;
        if s[i] != c {
            println!("{}to{}", c, s[i]);
        }
    }
}