# I use glot.io instead of gist.github so you can execute the code
# directly in browser
def flatten(array)
raise ArgumentError, "array must not be nil" if array.nil?
array.inject([]) do |result, element|
result = if element.kind_of?(Array)
element = flatten(element)
result.concat(element)
else
result << element
end
end
end
test_array = [[1,2,[3]],4, [5,[6],[]]]
expected_array = [1,2,3,4,5,6]
array = flatten(test_array)
if expected_array == array
print("#{array}\n")
puts "Work as expected"
else
raise "Didn't work"
end
