July 25, 2014
Today’s exercise is an interview question from Career Cup. When I first saw the exercise, I thought it would be easy, but I had trouble writing a solution, so maybe it will a good exercise for all you readers, as well:
Given a positive integer, return all the ways that the integer can be represented by letters using the mapping 1 -> A, 2 -> B, …, 26 -> Z. For instance, the number 1234 can be represented by the words ABCD, AWD and LCD.
Your task is to write the program to generate words from numbers. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.