text: def max_product(card_lists):
      product = 1
      for cards in card_lists:
          product *= max(cards)
  
      return product
  
  
  # 테스트
  test_cards1 = [[1, 6, 5], [4, 2, 3]]
  print(max_product(test_cards1))
  
  test_cards2 = [[9, 7, 8], [9, 2, 3], [9, 8, 1], [2, 8, 3], [1, 3, 6], [7, 7, 4]]
  print(max_product(test_cards2))
  
  test_cards3 = [[1, 2, 3], [4, 6, 1], [8, 2, 4], [3, 2, 5], [5, 2, 3], [3, 2, 1]]
  print(max_product(test_cards3))
  
  test_cards4 = [[5, 5, 5], [4, 3, 5], [1, 1, 1], [9, 8, 3], [2, 8, 4], [5, 7, 4]]
  print(max_product(test_cards4))
  