Walkthrough

Solutions

# EASY

def get_evens(arr)
  arr.select { |element| element.even? }
end

def calculate_doubles(arr)
  arr.map {|el| el * 2}
end

def calculate_doubles!(arr)
  arr.map! {|el| el * 2}
end

def array_sum_with_index(arr)
  sum = 0

  arr.each_with_index do |number, index|
    sum += (number * index )
  end

  sum
end


# MEDIUM

def price_is_right(bids, actual_retail_price)
  lower_bids = bids.reject { |bid| bid > actual_retail_price}
  lower_bids.max
end

def at_least_n_factors(numbers, n)
  numbers.select { |number| num_factors(number) >= n }
end

def num_factors(number)
  (1..number).count { |n| number % n == 0 }
end


# HARD

def ordered_vowel_words(words)
  words.select do |word|
    ordered_vowel_word?(word)
  end
end

def ordered_vowel_word?(word)
  vowels = "aeiou"

  vowels_in_word = word.chars.select do |letter|
    vowels.include?(letter)
  end

  vowels_in_word == vowels_in_word.sort
end

def products_except_me(numbers)
  numbers.map.with_index do |num, idx|
    sub_array = numbers[0...idx] + numbers[(idx + 1)..-1]
    array_product(sub_array)
  end
end

def array_product(array)
  array.reduce(:*)
end