双十一作品登记选购

class InventoryManager:
    def __init__(self):
        self.inventory = {}

    def add_product(self, product_id, quantity):
        if product_id in self.inventory:
            self.inventory[product_id] += quantity
        else:
            self.inventory[product_id] = quantity

    def remove_product(self, product_id, quantity):
        if product_id in self.inventory and self.inventory[product_id] >= quantity:
            self.inventory[product_id] -= quantity
        else:
            print("Not enough stock!")

    def check_stock(self, product_id):
        return self.inventory.get(product_id, 0)

# 使用示例
inventory_manager = InventoryManager()
inventory_manager.add_product('P001', 100)
print(inventory_manager.check_stock('P001'))  # 输出: 100
inventory_manager.remove_product('P001', 50)
print(inventory_manager.check_stock('P001'))  # 输出: 50