Display Letter Hot Target in CF

Letters = Static "abcdefghijklmnopqrstuvwxyz"

get_letter_count :: IO ->> Int
Empty => Int IO.raw_input ""

get_letters :: Int ->> String
count => Letters[:count][::-1]

tiles_for_letters :: Int ->> Int
letters => 1 + 2 * (letters-1)

letter_at_index :: Int, String, Int, Int ->> Int
tiles, letters, i, target => letters[Int max (abs x - target) (abs y - target)]
    where y = i % tiles, x = i // tiles

display_line :: Int, [String], Int ->> IO
width, arr, x => IO.log <- arr[x*width : (x+1)*width]

do:
    lc = get_letter_count ()
    letters = get_letters lc
    tile_count = tiles_for_letters lc
    target = lc-1

    letter_at_index = letter_at_idx tile_count letters ?
    display = display_line tile_count ? ?

    arr = @ <- letter_at_index [0..tile_count**2]''0
    for x in [0..tile_count]:
        display arr x