class Decipherer{


	public static void main(String[] args) {
		String message1 = "0@sn9sirppa@#?ia'jgtvryko1" ;
		String message2 = "q8e?wsellecif@#?sel@#?setuotpazdsy0*b9+mw@x1vj" ;
		String message3 = "aopi?sedohtém@#?sedhtmg+p9l!" ;

		// messages which must be decifered
		System.out.println(decipher(message1)); // J'ai appris
		System.out.println(decipher(message2)); // toutes les ficelles
		System.out.println(decipher(message3)); // des méthodes

	}

	/*
	// Return the result of a decifered message
	// message : The message which must be decifered
	*/
	public static  String decipher(String message){
		final int START_SUBSTRING = 6 ;
		int keyNumber = (message.length() + 1) / 2 ;
		String messageSub = message.substring(START_SUBSTRING - 1 , START_SUBSTRING + keyNumber - 1 );
		String messageClean = messageSub.replace("@#?" , " ");
		String messageFinal = new StringBuilder(messageClean).reverse().toString();

		return messageFinal;
	}

}