To make telephone numbers easier to remember, some companies use letters to show

their telephone number. For example, the telephone number $438-5626$ can be shown as

GET LOAN using letters. In some cases, to make a telephone number meaningful,

companies might use more than seven letters. For example, $225-5466$ can be displayed

as CALL HOME, which uses eight letters. Write a C$++$ program that prompts the user to

enter a telephone number expressed in letters$($Can be uppercase$/$lowercase or both$)$ and

outputs the corresponding telephone number in digits. If the user enters more than seven

letters, then process only the first seven letters. Also, output the $-($hyphen$)$ after the third

digit. Allow the user to use uppercase and lowercase letters and spaces between words.

Moreover, your program should process as many telephone numbers as the user wants.