Crate exercism

Modules

• acronym
• all_your_base
• alphametics
• anagram
• armstrong
• beer_song
• bob
• collatz_conjecture
• custom_set
• diffie_hellman
• fizzy
• grains
• high_scores
• largest_series_product
• leap
• luhn
• luhn_from
• luhn_trait
• matching_brackets
• nth_prime
• palindrome
• perfect_numbers
• prime_factors
• proverb
• raindrops
• reverse
• series
• squares
• sublist
• sum_of_multiples