Quick question , for here in the end , I try to ask user "Do you want to continue (Type y or n)". I have user input y to be continue ,however if user input anything else the program will just exit.

What if I want this program input y to be continue ,input n to exit, but if you input anything else it will show" you need to enter the right command" and re-ask "Do you want to continue (Type y or n)"

import java.util.Scanner;

public class driver {

public static void main(String[] args){

double a = 0,b = 0,c = 0;

char ch = ' ';

do{

Scanner scanner = new Scanner(System.in);

boolean bError = true;

while (bError)

{

System.out.println("Enter the value of a!");

if (scanner.hasNextDouble())

{

a = scanner.nextDouble();

}

else

{

System.out.println("Entered Non-numeric value, please enter correct value of a!");

scanner.next();

continue;

}

bError = false;

if(a == 0)

{

bError = true;

System.out.println("Error, Please do not enter a = 0!");

}

}

bError = true;

while(bError)

{

System.out.println("Enter the value of b!");

if (scanner.hasNextDouble())

{

b = scanner.nextDouble();

}

else

{

System.out.println("Entered Non-numeric value, please enter correct value of b!");

scanner.next();

continue;

}

bError = false;

}

bError = true;

while(bError)

{

System.out.println("Enter the value of c!");

if (scanner.hasNextDouble())

{

c = scanner.nextDouble();

}

else

{

System.out.println("Entered Non-numeric value, please enter correct value of c!");

scanner.next();

continue;

}

bError = false;

}

if( (b*b - 4*a*c) < 0)

{

System.out.println("Your input has no solution! please try again");

}

else

{

double r1 = ( -b + Math.sqrt(b*b - 4*a*c) ) /(2*a);

double r2 = ( -b - Math.sqrt(b*b - 4*a*c) ) /(2*a);

System.out.println("Root1 = "+ r1 + " Root2 = " + r2 + " ");

}

System.out.print(" Do you want to continue (Type y or n): ");

ch = scanner.next().charAt(0);

System.out.println();

} while (ch == 'Y' || ch == 'y');

System.out.print("Bye!");

}

}