Kata

A bookseller has lots of books classified in 26 categories labeled A, B, C, ..., Z. Each book has a code of at least 3 characters. The 1st character of a code is a capital letter which defines the book category.

In the bookseller's stocklist each code is followed by a space and by a positive integer, which indicates the quantity of books of this code in stock.

Task

You will receive the bookseller's stocklist and a list of categories. Your task is to find the total number of books in the bookseller's stocklist, with the category codes in the list of categories. Note: the codes are in the same order in both lists.

Return the result as a string described in the example below, or as a list of pairs (Haskell/Clojure/Racket/Prolog).

If any of the input lists is empty, return an empty string, or an empty array/list (Clojure/Racket/Prolog).

Example

# the bookseller's stocklist:
"ABART 20", "CDXEF 50", "BKWRK 25", "BTSQZ 89", "DRTYM 60"

# list of categories: 
"A", "B", "C", "W"

# result:
"(A : 20) - (B : 114) - (C : 50) - (W : 0)"

Explanation:

• category A: 20 books (ABART)
• category B: 114 books = 25 (BKWRK) + 89 (BTSQZ)
• category C: 50 books (CDXEF)
• category W: 0 books