class Caesar_Cipher
	def initialize(plain, cipher_step)
		@plain = plain
		@cipher_step = cipher_step
		@crypted = crypt(@plain, @cipher_step)
	end
 
	def crypt(plain, cipher_step)
		letters = plain.split(//)
		letters.map do |letter|
			if letter.scan(/\w/).length == 1
 
				cipher_step.times do
					if (letter != 'z') && (letter != 'Z')
						letter.next!
					elsif (letter == 'z')
						letter = 'a'
					elsif (letter == 'Z')
						letter = 'A'
					end
				end
			end
		end
 
		letters.join("")
	end
 
	def out
		puts @crypted
	end
end
 
mydecl = Caesar_Cipher.new("What a string!", 5)
mydecl.out

Y2xhc3MgQ2Flc2FyX0NpcGhlcgoJZGVmIGluaXRpYWxpemUocGxhaW4sIGNpcGhlcl9zdGVwKQoJCUBwbGFpbiA9IHBsYWluCgkJQGNpcGhlcl9zdGVwID0gY2lwaGVyX3N0ZXAKCQlAY3J5cHRlZCA9IGNyeXB0KEBwbGFpbiwgQGNpcGhlcl9zdGVwKQoJZW5kCgoJZGVmIGNyeXB0KHBsYWluLCBjaXBoZXJfc3RlcCkKCQlsZXR0ZXJzID0gcGxhaW4uc3BsaXQoLy8pCgkJbGV0dGVycy5tYXAgZG8gfGxldHRlcnwKCQkJaWYgbGV0dGVyLnNjYW4oL1x3LykubGVuZ3RoID09IDEKCgkJCQljaXBoZXJfc3RlcC50aW1lcyBkbwoJCQkJCWlmIChsZXR0ZXIgIT0gJ3onKSAmJiAobGV0dGVyICE9ICdaJykKCQkJCQkJbGV0dGVyLm5leHQhCgkJCQkJZWxzaWYgKGxldHRlciA9PSAneicpCgkJCQkJCWxldHRlciA9ICdhJwoJCQkJCWVsc2lmIChsZXR0ZXIgPT0gJ1onKQoJCQkJCQlsZXR0ZXIgPSAnQScKCQkJCQllbmQKCQkJCWVuZAoJCQllbmQKCQllbmQKCgkJbGV0dGVycy5qb2luKCIiKQoJZW5kCgoJZGVmIG91dAoJCXB1dHMgQGNyeXB0ZWQKCWVuZAplbmQKCm15ZGVjbCA9IENhZXNhcl9DaXBoZXIubmV3KCJXaGF0IGEgc3RyaW5nISIsIDUpCm15ZGVjbC5vdXQ=