import java.util.*;
public class PlayFairAlgorithm{
    public static void main(String args[]){
        System.out.println("Would you like to: \n1. Generate a Random Grid\n2. Use a Predefined Grid\n3. Encrypt a sentence\n4. Decrypt a Sentence\n5. Exit");
        Scanner keyb= new Scanner(System.in);
        int cho= keyb.nextInt();
        char m[][]={{'z', 'c', 'b', 'm', 'x'},
                    {'v', 'n', 'a', 'g', 'l'},
                    {'s', 'f', 'h', 'k', 'q'},
                    {'e', 't', 'u', 'o', 'w'},
                    {'r', 'y', 'i', 'p', 'd'}};

        while(cho!=5){
            if(cho==1){

            }
            else if(cho==2){
                char d[][]={{'z', 'c', 'b', 'm', 'x'},
                    {'v', 'n', 'a', 'g', 'l'},
                    {'s', 'f', 'h', 'k', 'q'},
                    {'e', 't', 'u', 'o', 'w'},
                    {'r', 'y', 'i', 'p', 'd'}};
                m=d;
                System.out.println("Would you like to: \n1. Generate a Random Grid\n2. Use a Predefined Grid\n3. Encrypt a sentence\n4. Decrypt a Sentence\n5. Exit");
                cho= keyb.nextInt();
            }
            else if(cho==3){
                System.out.println("Enter a sentence: ");
                Scanner keyc = new Scanner(System.in);
                String sent=keyc.nextLine();
                sent=sent.replaceAll(" ", "");
                char duped='z';
                for (int c = 1; c<sent.length();c+=2){
                    if(sent.charAt(c-1)==sent.charAt(c)){
                        duped=sent.charAt(c);
                    }
                    sent=sent.replace(new String(duped)+new String(duped), new String(duped)+'x'+new String(duped));
                }
                System.out.println(sent);
            }
            else if(cho==4){

            }
        }
    }
}