Question

我是Python的新手，因此决定在TestDome做些运动。以下是该网站上easy question的代码，但是由于它没有按原样打印结果，因此我得到零分。

class IceCreamMachine:
all={}
def __init__(self, ingredients, toppings):
    self.ingredients = ingredients
    self.toppings = toppings

def scoops(self):
    for i in range(0,len(self.ingredients)):
        for j in range(0,len(self.toppings)):
            print ([self.ingredients[i],self.toppings[j]])

machine = IceCreamMachine(["vanilla", "chocolate"], ["chocolate sauce"])
print(machine.scoops()) #should print[['vanilla', 'chocolate sauce'], ['chocolate', 'chocolate sauce']]

有人可以提示如何修复它吗？

Answer 1

看起来您需要返回值。

尝试：

class IceCreamMachine:
    all={}
    def __init__(self, ingredients, toppings):
        self.ingredients = ingredients
        self.toppings = toppings

    def scoops(self):
        res = []
        for i in self.ingredients:
            for j in self.toppings:
                res.append([i, j])
        return res

machine = IceCreamMachine(["vanilla", "chocolate"], ["chocolate sauce"])
print(machine.scoops())

Answer 2

针对此问题，我什至有一个较短的代码版本。我正在使用列表理解来解决此问题：

class IceCreamMachine:
    
    def __init__(self, ingredients, toppings):
        self.ingredients = ingredients
        self.toppings = toppings
        
    def scoops(self):
        return [[i,j] for i in self.ingredients for j in self.toppings]

machine = IceCreamMachine(["vanilla", "chocolate"], ["chocolate sauce"])
print(machine.scoops()) #should print[['vanilla', 'chocolate sauce'], ['chocolate', 'chocolate sauce']]

Answer 3

您无需使用for i in range(0,len(self.ingredients)):之类的范围，而只需使用 for i in elements并从两个列表中获取每个元素并追加到新列表中。（在这种情况下为k）。

class IceCreamMachine:

    def __init__(self, ingredients, toppings):
        self.ingredients = ingredients
        self.toppings = toppings

    def scoops(self):
        k=[]
        for i in self.ingredients:
            for j in self.toppings:
               k.append([i,j])
        return k

machine = IceCreamMachine(["vanilla", "chocolate"], ["chocolate sauce"])
print(machine.scoops()) #should print[['vanilla', 'chocolate sauce'], ['chocolate', 'chocolate sauce']]

用Python打印字符串（TestDome）

3 个答案: