In ancient Rome, emperor Julius Caesar used a code to its private correspondence. In this code, each letter in the message was replaced by a letter some fixed number of positions down the alphabet. For example, with a shift of 3, D would be replaced by A, E would become B, and so on.

Your task is now to discover the following message, but before doing so, you will have to discover the shift used to cypher it.

This is the message:

mjd

rd knwxy kqt xyju bfsy f ltqi inllnsl btrfs

rtsjd hfxm kqtb fqq gnl kfhji mtsjdx

kwtsynsl ts ymj kqttw lty ymjr i-gtdx wzssnsl

xmtwyd lty gtym gwtpj hfssty xjj bmfy nx htrnsl

bjfw ymjr fuuqj gtyytrx, bjfw ymjr fuuqj gtyytrx mtsjd

itqhj fsi lfggfsf fsi xmj ljy zu ts rd rtsjd

qtznj ymfy x*** lzhhn, kjsin, fsi ymj rtsjd

xjj ymj hfwwtyx ts mjw bwnxy stb xmj unrux gzlx gzssd

zxji yt ifyj pfsdj stb xmj bfsy rj

bmnqj n lty rd oznhj bfssf yfpj rd to

ny fnsy mjw gnwymifd bnym mjw sfrj ts f hfpj

nk n jajw uqfd ktw lwfij f

lty dtz xyzhp ts rd

ts rd jqjafytw

ljy ny zu, ts rd jqjafytw

hmjhp ny tzy

knwxy kqttw, xyzhp ts ymj ltqi inlljw

xjhtsi kqttw, xyzhp ts ymj inrj unjhj

ymnwi kqttw, xyzhp ts ymj mtti wfy

ktzwym kqttw, kwjfp ny n it sty pstb hfzxj

You can use this JAVA file to begin with your work.

import java.util.Scanner;

import java.io.File;

public class Caesar {

public static void main(String[] args) throws Exception {

String filename = "mistery.txt";

Scanner sc = new Scanner(new File(filename));

String content = "";

while (sc.hasNext()) {

content += sc.nextLine() + " ";

}

//PUT YOUR CODE HERE

System.out.println(content);

}

/**

* Function to apply a shift to a letter in the alphabet

* @param letter: The letter to use

* @param offset: The shift to apply. This must be a positive number

*/

public static char convert(char letter, int offset) {

if (offset < 0) {

System.out.println("The offset must be positive");

return letter;

}

else if (letter >= 'a' && letter <= 'z') {

int size = 'z'-'a'+1;

int pos = letter - 'a';

pos = (pos + offset) % size;

return (char)(pos + 'a');

}

return letter;

}

}