difficulty: 1
[X] - simple-linked-list
[X] - two-fer
[X] - resistor-color
difficulty: 2
[X] - rna-transcription
[X] - word-count
[X] - bob
[X] - nucleotide-count
[X] - secret-handshake
[X] - rotational-cipher
[X] - strain
[X] - protein-translation
[X] - pig-latin
[X] - space-age
[X] - accumulate
[X] - acronym
[X] - series
[X] - raindrops
[X] - run-length-encoding
[X] - sublist
[X] - scrabble-score
[X] - sum-of-multiples
[X] - pangram
[X] - anagram
[X] - nth-prime
[X] - all-your-base
[X] - hamming
[X] - triangle
[X] - etl
[X] - collatz-conjecture
[ ] - armstrong-numbers (block)
[X] - roman-numerals
difficulty: 3
[ ] - grep (block)
[X] - beer-song
[X] - twelve-days
[X] - matrix
[X] - matching-brackets
[X] - phone-number
[X] - isogram
[X] - grade-school
[X] - leap
[x] - grains
[x] - change
[X] - binary
[X] - gigasecond
[ ] - pascals-triangle
[ ] - hexadecimal
[X] - binary-search
[ ] - binary-search-tree
[X] - prime-factors
[X] - perfect-numbers
[ ] - atbash-cipher (block)
[ ] - simple-cipher (block)
[ ] - say
[X] - isbn-verifier
[X] - dnd-character
[X] - flatten-array
[ ] - kindergarten-garden
difficulty: 4
[X] - list-ops
[ ] - tournament
[ ] - meetup
[X] - parallel-letter-frequency
[ ] - diffie-hellman
[ ] - largest-series-product (block)
[ ] - crypto-square (block)
[ ] - allergies (block)
[ ] - difference-of-squares (block)
[ ] - dominoes (block)
[ ] - spiral-matrix
difficulty: 5
[X] - markdown
[ ] - luhn
[ ] - saddle-points
[ ] - diamond
[ ] - sieve (block)
[ ] - pythagorean-triplet (block)
[ ] - palindrome-products
[ ] - custom-set
[ ] - transpose
[ ] - alphametics (block)
[ ] - clock (block)
[ ] - scale-generator
difficulty: 6
[X] - robot-simulator
[ ] - wordy (block)
[ ] - rail-fence-cipher
[ ] - ocr-numbers
difficulty: 7
[X] - bank-account
[ ] - queen-attack
[ ] - minesweeper
[ ] - connect
[ ] - poker (block)
difficulty: 8
[X] - zipper
[ ] - bowling
[ ] - dot-dsl (block)
difficulty: 10
[ ] - forth (block)
