gold_mine

number_of_locations = int(input())

for each_location in range(number_of_locations):
    expected_average_gold_per_day = float(input())
    days_of_work = int(input())
    total_gold_for_each_location = 0
    for each_day in range(days_of_work):
        daily_gold = float(input())
        total_gold_for_each_location += daily_gold
    average_gold_per_location = total_gold_for_each_location / days_of_work
    if average_gold_per_location >= expected_average_gold_per_day:
        print(f"Good job! Average gold per day: {average_gold_per_location:.2f}.")
    else:
        print(f"You need {expected_average_gold_per_day - average_gold_per_location:.2f} gold.")