02. Treasure Hunt (Stoqnow)

def check_index(list_name: list, index_num: int):
    if 0 <= index_num < len(list_name):
        return True
    else:
        return False


initial_treasure_list = input().split('|')
command = input()

while not command == 'Yohoho!':
    command = command.split()
    command_type = command[0]
    if command_type == 'Loot':
        for index in range(1, len(command)):
            item = command[index]
            if item not in initial_treasure_list:
                initial_treasure_list.insert(0, item)
    elif command_type == 'Drop':
        given_index = int(command[1])
        if check_index(initial_treasure_list, given_index):
            initial_treasure_list.append(initial_treasure_list.pop(given_index))
    elif command_type == 'Steal':
        stolen_items_list = []
        given_num = int(command[1])
        if len(initial_treasure_list) <= given_num:
            stolen_items_list = initial_treasure_list
            initial_treasure_list = []
        else:
            stolen_items_list = initial_treasure_list[len(initial_treasure_list) - given_num:]
            initial_treasure_list = initial_treasure_list[:len(initial_treasure_list) - given_num]
        print(', '.join(stolen_items_list))
    command = input()

total_sum = 0
if not initial_treasure_list:
    print('Failed treasure hunt.')
else:
    for element in initial_treasure_list:
        total_sum += len(element)
    average_gain = total_sum / len(initial_treasure_list)
    print(f"Average treasure gain: {average_gain:.2f} pirate credits.")