MAX_ITEMS = 15

def has_space(boat, item_count):
    if len(boat) + item_count <= MAX_ITEMS:
        return True
    else:
        return False
    # Instead of this if-else structure, you could just write
    # return len(boat) + item_count <= MAX_ITEMS

def add_to_boat(boat, item_count, item_name):
    i = 0
    for i in range(item_count):
        boat.append(item_name)
    return boat

def avg_all_items(b1, b2, mass):
    item_count = len(b1) + len(b2)
    if item_count == 0:
        return 0
    avg = mass / item_count
    return avg

def main():
    boat1 = []
    boat2 = []
    mass_boat1 = 0
    mass_boat2 = 0
    print("Enter items. Stop by entering a non-positive number of items.")
    full_boat1 = False
    full_boat2 = False
    number_of_items = int(input("Enter the number of the items:\n"))

    while number_of_items > 0 and (not full_boat1 or not full_boat2):
        name = input("Enter the name of the items:\n")
        mass = int(input("Enter the mass of one item (kg):\n"))
        if mass_boat1 <= mass_boat2 and has_space(boat1, number_of_items):
            boat1 = add_to_boat(boat1, number_of_items, name)
            mass_boat1 += number_of_items * mass
        elif has_space(boat2, number_of_items):
            boat2 = add_to_boat(boat2, number_of_items, name)
            mass_boat2 += number_of_items * mass
        elif has_space(boat1, number_of_items):
            boat1 = add_to_boat(boat1, number_of_items, name)
            mass_boat1 += number_of_items * mass
        else:
            print("There is not enough space for so many items.")
        if len(boat1) == MAX_ITEMS:
            full_boat1 = True
        if len(boat2) == MAX_ITEMS:
            full_boat2 = True
        if not full_boat1 or not full_boat2:
            number_of_items = int(input("Enter the number of the items:\n"))

    print(f"Boat number 1 has items {boat1}\nand it weighs {mass_boat1} kg.")
    print(f"Boat number 2 has items {boat2}\nand it weighs {mass_boat2} kg.")
    total_mass = mass_boat1 + mass_boat2
    avg_item_mass = avg_all_items(boat1, boat2, total_mass)
    print(f"The average weight of an item is {avg_item_mass:.1f} kg.")

main()