如何解决ppython中的循环问题

Question

大家好，我是这里新来的，我也在为我的大学学习python，我被困在这个问题上，我必须创建一个星期的日子列表，把每周的天数和英里数，然后我必须做总数和计算汽油的费用，但我需要插入循环并告诉程序是值小于0返回并再次插入值。这是我的问题，如果有人能帮我，我会很高兴的。谢谢。

myDay = day1, day2, day3, day4, day5, day6, day7

day1 = int(input("Enter miles for Monday:"))
day2 = int(input("Enter miles for Tuesday:"))
day3 = int(input("Enter miles for Wednesday:"))
day4 = int(input("Enter miles for Thursday:"))
day5 = int(input("Enter miles for Friday:"))
day6 = int(input("Enter miles for Saturday:"))
day7 = int(input("Enter miles for Sunday:"))

if myDay <= 0:
    print("that number is wrong, select a number superior then 0")
    myDay = int(input("Try again"))

total = day1 + day2 + day3 + day4 + day5 + day6 + day7
print("The total mileage is", total)

print("Cost of petrol", total * 1.35 / 11.2)

Answer 1

通过创建一个函数，您可以简单地添加一个会在不满足条件时重试的时间。

def new_day(day_name):
    day = 0
    first = True
    while day <= 0:
        if first:
            first = False
        else:
            print("that number is wrong, select a number superior then 0")
        day = int(input(f"Enter miles for {day_name}:"))

    return day


day1 = new_day("Monday")
day2 = new_day("Tuesday:")
day3 = new_day("Wednesday:")
day4 = new_day("Thursday:")
day5 = new_day("Friday:")
day6 = new_day("Saturday:")
day7 = new_day("Sunday:")

total = day1 + day2 + day3 + day4 + day5 + day6 + day7
print("The total mileage is", total)

print("Cost of petrol", total * 1.35 / 11.2)

编辑:通过建议@aneroid使用dict理解一串日子，简化了代码：

def new_day(day_name):
    day = 0
    first = True
    while day <= 0:
        if first:
            first = False
        else:
            print("that number is wrong, select a number superior then 0")
        day = int(input(f"Enter miles for {day_name}:"))

    return day


days = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"]

day_miles = {day: new_day(day) for day in days}
total = sum(day_miles.values())
print("The total mileage is", total)

print("Cost of petrol", total * 1.35 / 11.2)

Answer 2

你好，我也是蟒蛇学习方面的新手，所以我认为这就是解决办法：

day1=int(input('Enter miles:'))
day2=int(input('Enter miles:'))

weekday=[day1, day2]

for i in weekday:
  if i<=0:
    print('that number is wrong, type another one:')
    i=int(input('write:'))
    weekday.append(i)

total=sum(weekday)
print(total)
print(total*1.35/11.2)