class Product:
    def __init__(self, name, price):
        self.name = name
        self.price = price


class Cart:
    def __init__(self):
        self.products = []

    def add_product(self, product):
        self.products.append(product)

    def get_total_amount(self):
        return sum(product.price for product in self.products)


class User:
    def __init__(self, name, points):
        self.name = name
        self.points = points
        self.cart = Cart()

    def checkout(self, coupon_rate=0):
        total_amount = self.cart.get_total_amount()

        discount_amount = int(total_amount * coupon_rate)
        after_coupon_amount = total_amount - discount_amount

        max_point_usage = int(after_coupon_amount * 0.1)
        point_used = min(self.points, max_point_usage)

        final_amount = after_coupon_amount - point_used

        self.points -= point_used

        return (
            f"총액 {total_amount:,}원에서 쿠폰 할인({discount_amount:,}원)이 적용되었습니다. "
            f"포인트 {point_used:,}점을 추가 사용하여 최종 결제 금액은 {final_amount:,}원입니다."
        )


user = User("홍길동", 15000)

user.cart.add_product(Product("상품A", 50000))
user.cart.add_product(Product("상품B", 30000))

result = user.checkout(coupon_rate=0.1)

print(result)