Question

能不能帮我解决我的问题，如果它不在列表中或不在同一索引点，请让我输入另一个权重。谢谢您的帮助。这是我的代码：

coins = [2, 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01]

weights = [120, 175, 160, 250, 325, 325, 356, 356]

a = []
found = False
foundd = False
loop = "yes"
bags = 0
ans = "no"
ansb = "no"
coina = 0


while loop == "yes":

    name = input("What is your name?")

    coin = float(input("What coin is it?"))

    weight = float(input("How much does the bag weigh?"))

    for x in coins:
        if coin == x:
            found = True
            print("coin right")

        if found == False:
            print("coin wrong")


    if weights.index(weight)==coins.index(coin):
        foundd = True
        print("weight right")
    else:
        print("weight wrong")

    coina = coina + coin
    bags += 1

    newList = [name, coin, weight]

    a.append (newList)

    ans = input("Do you want to see the list with everyones names and amount of coins with weight?(yes?/no)")
    ansb = input("Do you want to see amount of bags put in and coin value?(yes/no)")

    if ans == "yes":
        for i in a:
            print(i)
    if ansb == "yes":
        print(bags,"£",coina)


    loop = input("Do you want to enter another coin?(yes/no)")

（忽略它，除非我写更多，否则它不会让我发布。）

Answer 1

您应该尝试：

coins = [2, 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01]

weights = [120, 175, 160, 250, 325, 325, 356, 356]

a = []
found = False
foundd = False
loop = "yes"
bags = 0
ans = "no"
ansb = "no"
coina = 0


while loop == "yes":

    name = input("What is your name?")

    #ask for coin and check if it is in the list...
    coin = float(input("What coin is it?"))
    try: 
        coins.index(coin)
    except:
        print('Coin not in the list...')
        coin = float(input("What coin is it?"))

    #ask for weight and check if it is in the list...
    weight = float(input("How much does the bag weigh?"))
    try: 
        weights.index(weight)
    except:
        print('Weight not in the list...')
        weight = float(input("How much does the bag weigh?"))

    for x in coins:
        if coin == x:
            found = True
            print("coin right")

        if found == False:
            print("coin wrong")

    if weights.index(weight)==coins.index(coin):
        foundd = True
        print("weight right")
    else:
        print("weight wrong")
[...]

问题是您只能犯一个错误。

我觉得最简单的方法是使用for循环来实现自己的索引函数。如果找不到该元素，此函数将返回索引或None。这样，您可以要求用户输入while的值为None。

Answer 2

dicta = { 
    2: 120, 1: 175, 0.5: 160, 0.2: 250, 0.1: 325, 0.05: 325,0.02: 356, 0.01: 356
}

while True:
    name = input("What is your name? ")

    coin = 'a'    
    while coin not in dicta.keys():
        try:
            coin = float(input("What coin is it ?"))
        except ValueError:
            print("Not a valid input")

    weight = 'a'    
    while weight not in dicta.values():
        try:
            weight = float(input("How much does the bag weigh?"))
        except ValueError:
            print("Not a valid input")

    if weight == dicta[coin]:
        print("Weight right.")
    else:
        print("Weight wrong")

I would suggest building off a skeleton like this, also you should look into try, except and how you are applying them

如果输入的重量不在列表中，如何使它不出错（索引错误）

2 个答案: