#[macro_use]
extern crate log;
extern crate env_logger;
extern crate rustc_serialize;

use rustc_serialize::hex::FromHex;
use std::io::{BufRead, stdin};
use std::iter::repeat;

fn score(plaintext: &Vec<u8>) -> u32 {
    let ranking = [24, 7, 15, 17, 26, 11, 10, 19, 22, 4, 5, 16, 13,
                   21, 23, 8, 2, 18, 20, 25, 14, 6, 12, 3, 9, 1];
    let mut score = 0;

    for ch in plaintext.iter() {
        if ch >= &97 && ch <= &122 {
            score += ranking[(ch - 97) as usize];
        }
    }
    score
}

fn main() {
    env_logger::init().unwrap();
    let stdin = stdin();
    let mut maxscore = 0;
    let mut decrypted: Vec<u8> = vec![];

    for line in stdin.lock().lines().filter_map(|x| x.ok()) {
        match line.from_hex() {
            Ok(ciphertext) => {
                for key in 0..0xff {
                    let plaintext: Vec<u8> = ciphertext.iter().zip(repeat(key)).map(|(c, k)| c ^ k).collect();
                    let s = score(&plaintext);
                    if s > maxscore {
                        maxscore = s;
                        decrypted = plaintext;
                    }
                }
            }
            Err(e) => error!("{}", e)
        }
    }
    match String::from_utf8(decrypted) {
        Ok(s) => println!("{}", s),
        Err(e) => error!("{}", e)
    }
}