Ask the user to input two numbers using the Scanner class.
Display the menu options for the calculator program.
Ask the user to press 0 to quit.
Ask the user to press 1 to add.
Ask the user to press 2 to subtract.
Ask the user to press 3 to multiply.
Ask the user to press 4 to divide.
Perform the correct calculation based on user input and display the result.
Display an error message if the user enters an invalid input.
Repeat the process until the user chooses to quit.