The international standard letter/number mapping for telephones is shown in Exercise. Writ...

The international standard letter/number mapping for telephones is shown in Exercise. Write a method that returns a number, given an uppercase letter, as follows:

int getNumber(char uppercaseLetter)

Write a test program that prompts the user to enter a phone number as a string. The input number may contain letters. The program translates a letter (uppercase or lowercase) to a digit and leaves all other characters intact. Here is a sample run of the program:

The international standard letter/number mapping found on the telephone is shown below:

Write a program that prompts the user to enter a letter and displays its corresponding number.