daveed/find duplicate elements in an array

## find duplicate elements in an array
module Enumerable
  def dups
    inject({}) {|h,v| h[v]=h[v].to_i+1; h}.reject{|k,v| v==1}.keys
  end
end

# arr = [2,8,8,42,7,33,42]
# puts arr.dups.inspect
# [8, 42]
	module Enumerable
	def dups
	inject({}) {\|h,v\| h[v]=h[v].to_i+1; h}.reject{\|k,v\| v==1}.keys
	end
	end

	# arr = [2,8,8,42,7,33,42]
	# puts arr.dups.inspect
	# [8, 42]