Kata

You should write a function that takes two string values: string_a and string_b, and returns a string which is the equivalent of multiplying the the numerical values of the two strings together.

To elaborate, if string_a was 'abcde' and string_b was 'ghijk'**, you would end up with 01234 * 678910 and the final result would be 'idhhhejea':

the_solution('abcde', 'ghijk') == 'idhhhejea'  # true

Your code should ignore all non_letters and should be case-insensitive. If the one of the string is empty, your function should return 0. You can also assume the string will have no spaces.

All the best.

** If the numerical value of a letter is 10 or higher, you should take both the digits as with the example above where 'ghijk' becomes 678910.