use std::io::{self, BufRead};

fn main() {
    let stdin = io::stdin();
    let mut line = String::new();
    stdin.lock().read_line(&mut line).unwrap();
    let a = line.trim();

    let n = a.len();
    for i in 0..=n {
        let b = &a[..i];
        let x = format!("{}{}", a, b.chars().rev().collect::<String>());
        if x == x.chars().rev().collect::<String>() {
            println!("{}", x);
            return;
        }
    }
}