Problem 3: [10 marks] Phone key pads (filename: PhoneKeyPads.java)

Design an algorithm and then write a program that prompts the user to enter a letter (uppercase or lowercase) and displays its corresponding number on the console. When the character is not a letter, display an error message and use System.exit(0) to terminate the program. Use a switch statement.

Below are some sample runs:

Enter a letter (uppercase or lowercase): A

A is on the number key 2

Enter a letter (uppercase or lowercase): a

a is on the number key 2

Enter a letter (uppercase or lowercase): +

+ is an invalid input