备案代金卷

def apply_voucher(total_amount, voucher_code):
    # 假设有一个函数来验证和使用代金券
    voucher_info = validate_voucher(voucher_code)
    if voucher_info and voucher_info['valid']:
        discount_amount = min(total_amount, voucher_info['amount'])
        total_amount -= discount_amount
        print(f"代金券 {voucher_code} 已成功使用，减免金额: {discount_amount}")
    else:
        print("代金券无效或已过期")
    return total_amount

def validate_voucher(voucher_code):
    # 这里应该有实际的逻辑去数据库或API验证代金券
    # 假设返回一个包含代金券信息的字典
    vouchers = {
        "VOUCHER123": {"amount": 50, "valid": True},
        "VOUCHER456": {"amount": 0, "valid": False}
    }
    return vouchers.get(voucher_code, {"amount": 0, "valid": False})

# 示例使用
total = 100
voucher = "VOUCHER123"
final_amount = apply_voucher(total, voucher)
print(f"最终需支付金额: {final_amount}")