ESAAS HW0 Part 2

hw0-part1.rb

# using string interpolation
def hello(name)
  "Hello, #{name}"
end

# I first check if the first letter is alphabetical
# then see if the first lower case letter is a vowel
# and return the opposite of that boolean
def starts_with_consonant?(s)
  return false unless s[/^[a-z]/i]
  not %(a e i o u).include? s.downcase[0].to_s
end

# I do an empty string check first
# then I see if it's a valid binary representation by
# checking that all chars are either 1 or 0
# finally I convert the string into integer using base 2
# conversion, then a quick modulus check with 4, 0 means it
# its a multiple.
def binary_multiple_of_4?(s)
  return false if s == ''
  s.split('').uniq.all? { |i| i == '0' || i == '1' } \
    && s.to_i(2) % 4 == 0
end