jc99kuo

-- Answers for Prerequisites in FLOLAC 2018

-- 1) myFst

myFst :: (a, b) -> a
myFst (x, _) = x

-- 2) myOdd

myOdd :: Int -> Bool

jc99kuo

--  FLOLAC 2018 Week 4 -- Caesar Cipher & Decipher

module CaesarCipher (encode, decode) where

import Data.List

letStart = 'A'
letFinal = 'Z'
letSeque = [letStart .. letFinal]
letQty = length letSeque

jc99kuo

--  FLOLAC 2018 Week 3 -- Goldbach's conjecture

-- A simple, intuitive, straight fowward solution.
-- And may be not so efficient.  :-)   

goldbach :: Int -> Maybe (Int, Int)

goldbach nn 
    | nn < 3  = Nothing
    | odd nn  = Nothing

jc99kuo

--  FLOLAC 2018 Week 2 -- Histogram

histogram :: [Int] -> String

histogram ix =
       concat [ row n | n <- [heigh, heigh - 1  .. 1]] ++
       "==========\n"  ++
       "0123456789\n"
    where 
       row m = [ if mm < m then ' ' else '*' | mm <- accl ] ++ "\n" 

jc99kuo

--  FLOLAC 2018 Week 1 -- nub: filter out duplicating integers on a list

nub :: [Int] -> [Int]

nub ix = dedup [] ix 
  where 
    dedup = \xs ys -> 
      case ys of 
        [] -> xs
        (yhead:ytail) ->