Question

WAP to accept 10 phone numbers and accept a phone number from the user, only the first four digits of the phone number and display all the phone numbers of the array in which are having those first four digits​

Answer 1

Answer:

Before the advent of QWERTY keyboards, texts and numbers were placed on the same key. For example, 2 has “ABC” if we wanted to write anything starting with ‘A’ we need to type key 2 once. If we wanted to type ‘B’, press key 2 twice and thrice for typing ‘C’. Below is a picture of such a keypad.

Mobile-keypad

Given a keypad as shown in the diagram, and an n digit number, list all words which are possible by pressing these numbers.