Find the sum into a sequence

find_sums.rb

# Create a funtion that shows the pair of numbers that return the same results
# as expected. In the next format find_sums([1,2,3,4,5,6]. 12)


def find_sum(list, expected_result)
  list_index = []
  hash_list = {}
  list.each_with_index {|value, key| hash_list[key] = value  }

  hash_list.each do |item|
    seed = item

    hash_list.each do |item|
      if seed.first != item.first && seed.last + item.last == 12
        list_index << "#{seed.first} and #{item.first} (#{seed.last} + #{item.last} = 12)"
      end
    end
  end

  list_index
end


result = find_sum([1,3,5,4,7,9],12)
result.each{ |item| puts item }