Python如何根据用户输入的所选服务求和并打印账单总金额

你可以通过新增总金额累计变量、在判断服务类型的分支中累加对应价格的方式实现需求，改动非常小，具体如下：

修改后的完整代码 #

print("Fazli's Vet Services\n")
print("Exam: 50")
print("Vaccinations: 25")
print("Trim Nails: 5")
print("Bath: 20\n")

exam = "exam"
vaccinations = "vaccinations"
trim_nails = "trim nails"
bath = "bath"
none = "none"

exam_price = 50
vaccination_price = 25
trim_nails_price = 5
bath_price = 20
none_price = 0

# 新增总金额变量，初始值为0
total = 0

# 用户输入转小写，避免大小写不匹配的问题
first_service = input("Select first service:").lower()
second_service = input("Select second service:").lower()

print("\nFazli's Vet Invoice")

if first_service == exam:
    print("Service 1 - Exam: " + str(exam_price))
    total += exam_price
elif first_service == vaccinations:
    print("Service 1 - Vaccinations: " + str(vaccination_price))
    total += vaccination_price
elif first_service == trim_nails:
    print("Service 1 - Trim Nails: " + str(trim_nails_price))
    total += trim_nails_price
elif first_service == bath:
     print("Service 1 - Bath: " + str(bath_price))
     total += bath_price
elif first_service == none:
    print("Service 1 - None: " + str(none_price))
else:
    print("Service 1 - None: " + str(none_price))


if second_service == exam:
    print("Service 2 - Exam: " + str(exam_price))
    total += exam_price
elif second_service == vaccinations:
    print("Service 2 - Vaccinations: " + str(vaccination_price))
    total += vaccination_price
elif second_service == trim_nails:
    print("Service 2 - Trim Nails: " + str(trim_nails_price))
    total += trim_nails_price
elif second_service == bath:
     print("Service 2 - Bath: " + str(bath_price))
     total += bath_price
elif second_service == none:
    print("Service 2 - None: " + str(none_price))
else:
    print("Service 2 - None: " + str(none_price))

# 输出总金额
print(f"Total: {total}")

核心改动说明 #

• 新增total变量用于累计金额，初始值设为0
• 对用户输入的内容做小写转换，避免大小写不一致导致的匹配失败问题
• 在每个服务判断分支中，打印明细的同时把对应价格加到total变量
• 所有明细打印完成后，输出最终的总金额即可

运行代码后即可实现和示例完全一致的效果，选中服务的价格会自动累加输出。

内容的提问来源于stack exchange，提问作者Fazli Berisha