reverse.rb

def reverse_1(array)
  index = array.size - 1
  result = []
  
  for i in 0..index do
    result[index - i] = array[i]
  end
  
  result
end

def reverse_2(array)
  if array.size == 0
    array
  else
    reverse_2(array[1..-1]) + [array[0]] 
  end
end

puts reverse_1([1, 2, 3, 3]) == [3, 3, 2, 1]
puts reverse_2([1, 2, 3, 3]) == [3, 3, 2, 1]