import java.io.*;

public class NumberSystem {

    public static BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    public static int category,input;
    public static String reBin;
    public static int arr[] = new int[1];

    public static void main(String[] xxx) throws IOException {
        Category();
        Cases();
    }

    public static void Category() throws IOException
    {
        try {
            System.out.println("Please Input a Value that Given Below\n\t1 - Binary\n\t2 - Octal\n\t3 - Decimal\n\t4 - Hexadecimal\n\t5 - Exit\n\nEnter a Value: ");
            String a = in.readLine();
            category = Integer.parseInt(a);
            if(a.length() >= 2){
                Category();
            }else {
                Cases();
            }
        }catch(NumberFormatException d)
        {
            System.out.println("Syntax Error, Please Re-Input");
            Category();
        }
    }

    public static void Input() throws IOException
    {
            if(category == 4)
            {
                try{
                    System.out.print("Enter the value of your INPUT: ");
                    reBin = in.readLine();
                }catch(NumberFormatException daison){
                    System.out.println("Syntax Error, Please Re-Input");
                    Input();
                }
            }else{
                try{
                    System.out.print("Enter the value of your INPUT: ");
                    int a = Integer.parseInt(in.readLine());
                    input = a;
                    reBin = Integer.toString(a);
                }catch(NumberFormatException daison){
                    System.out.println("Syntax Error, Please Re-Input");
                    Input();
                }
            }
    }

    public static void Cases() throws IOException
    {
        switch(category)
        {
            case 1:
            case 2:
            case 3:
            case 4:
                    Input();
                    if(category == 1){Binary();}
                    else if(category == 2){Octal();}
                    else if(category == 3) {Decimal();}
                    else {Hex();}
                    break;
            case 5:
                    System.exit(0);
                    break;
            default:
                    try{
                        System.out.println("Syntax Error, Please Re-Input");
                        System.out.println("Please Input a Value that Given Below\n\t1 - Binary\n\t2 - Octal\n\t3 - Decimal\n\t4 - Hexadecimal\n\t5 - Exit\n\nEnter a Value: ");
                        String a = in.readLine();
                        category = Integer.parseInt(a);
                        if(a.length() >= 2) Category();
                    }catch(NumberFormatException daison) {
                        System.out.println("Syntax Error, Please Re-Input");
                        Cases();
                    }
                    break;
        }
    }

    public static void Binary() throws IOException
    {
        try{
                int a = Integer.parseInt(reBin, 2);
                String b = Integer.toOctalString(a);
                String c = Integer.toHexString(a).toUpperCase();
                PrintValues(0,1,1,1, "null",b,Integer.toString(a),c);
                ReTain();
        }catch(NumberFormatException daison)
        {
                System.out.print("Error!!, Please use 1 and 0\n");
                Cases();
        }
    }

    public static void Octal() throws IOException
    {
        try{
                int aaa = Integer.parseInt(reBin, 8);
                String bbb = Integer.toHexString(aaa).toUpperCase();
                String ccc = Integer.toBinaryString(aaa);
                PrintValues(1,0,1,1,ccc, "null",Integer.toString(aaa),bbb);
                ReTain();
        }catch(NumberFormatException daison)
        {
                System.out.print("Error!, Please do not use 8 and up!!\n");
                Cases();
        }
    }

    public static void Decimal() throws IOException
    {
        try{
                PrintValues(1,1,0,1, Integer.toBinaryString(input), Integer.toOctalString(input) , "null" , Integer.toHexString(input));
                ReTain();
        }catch(NumberFormatException daison)
        {
                System.out.print("Error!, please input a good amount!\n");
                Cases();
        }
    }

    public static void Hex() throws IOException
    {
        try{
                int aa = Integer.parseInt(reBin, 16);
                String bb = Integer.toOctalString(aa);
                String cc = Integer.toBinaryString(aa);
                PrintValues(1, 1, 1, 0, cc, bb, Integer.toString(aa), "null");
                ReTain();
        }catch(NumberFormatException daison)
        {
                System.out.print("There is an Error, Re-Input!!\n");
                Cases();
        }
    }

    public static void ReTain() throws IOException
    {
        System.out.print("Would you like to try Again? Y/N: ");
        char trytry = in.readLine().charAt(0);

        if(trytry == 'y' || trytry == 'Y'){ Category(); Cases(); }
        else if(trytry == 'n' || trytry == 'N'){ System.exit(1); }
        else{ System.out.println("Your input is Wrong!!!"); ReTain();}
    }

    public static void PrintValues(int w, int x, int y, int z, String val1, String val2, String val3, String val4)
    {
        if(w == 1)System.out.println("The Binary Value is: " + val1);
        if(x == 1)System.out.println("The Octal Value is: " + val2);
        if(y == 1)System.out.println("The Decimal Value is: " + val3);
        if(z == 1)System.out.println("The Hex Value is: " + val4);
    }
}