acronomize.rb

# def acronymize(sentence)
#   string = ""
#   sentence.split(" ").each do |word|
#     string += word[0].upcase
#   end
#   return string
# end

# redo using map


# []  {} .

def acronymize(sentence)
  sentence.split(" ").map { |word| word[0].upcase }.join
end

decrypt.rb

# modify encrypt so it can encrypt and decrypt using the same method
# and apply the permutation that we want, don't have to be 3

#  ||   []   {}   .  ;  :

def encrypt(text, num = -3)

  alphabet = ("A".."Z").to_a
  letters = text.upcase.split("")
  string = ""
  letters.each do |letter|
    index = alphabet.index(letter)
    if index.nil?
      string += letter
    else
      string += alphabet[(index + num) % 26]
    end
  end
  return string
end



def decrypt(text)
  # what code here
  encrypt(text, 3)
end

encrypted_text = "FK ZOVMQLDOXMEV, X ZXBPXO ZFMEBO, XIPL HKLTK XP ZXBPXO'P ZFMEBO, QEB PEFCQ ZFMEBO, ZXBPXO'P ZLAB LO ZXBPXO PEFCQ, FP LKB LC QEB PFJMIBPQ XKA JLPQ TFABIV HKLTK BKZOVMQFLK QBZEKFNRBP. FQ FP X QVMB LC PRYPQFQRQFLK ZFMEBO FK TEFZE BXZE IBQQBO FK QEB MIXFKQBUQ FP OBMIXZBA YV X IBQQBO PLJB CFUBA KRJYBO LC MLPFQFLKP ALTK QEB XIMEXYBQ. CLO BUXJMIB, TFQE X IBCQ PEFCQ LC 3, A TLRIA YB OBMIXZBA YV X, B TLRIA YBZLJB Y, XKA PL LK. QEB JBQELA FP KXJBA XCQBO GRIFRP ZXBPXO, TEL RPBA FQ FK EFP MOFSXQB ZLOOBPMLKABKZB."
puts decrypt(encrypted_text)

encrypt.rb

def encrypt(text)
  alphabet = ("A".."Z").to_a
  letters = text.upcase.split("")
  string = ""
  letters.each do |letter|
    index = alphabet.index(letter)
    if index.nil?
      string += letter
    else
      string += alphabet[index - 3]
    end
  end
  return string
end


# create method name encrypt that takes a parameter(string) called text

# create array containing alphabet

# split text in letters

# iterate on letters

# get index of letter

# check if index exists, if not return normal letter, if exist , apply rotation

# create string from array

puts encrypt("MethOd") == "JBQELA"