Question

这个代码应该在检查库存中是否有可用的物品（库存变量）之后计算所列物品总价格，我想知道为什么我不打印任何东西。

    shopping_list = ["banana", "orange", "apple"]

stock = {
    "banana": 6,
    "apple": 0,
    "orange": 32,
    "pear": 15
}

prices = {
    "banana": 4,
    "apple": 2,
    "orange": 1.5,
    "pear": 3
}

def compute_bill(food):
    total=0
    for i in food:
        if stock[i]>0:
            total+=prices[i]
    return total    
    print total
compute_bill(shopping_list)

Answer 1

您的打印需要在退货声明之前：

def compute_bill(food):
    total=0
    for i in food:
        if stock[i]>0:
            total+=prices[i]    
    print total
    return total

Answer 2

如果在IDE中运行，则需要使用print

print compute_bill(shopping_list)

返回语句后print total为unreachable。

所以要么忘记print，要么放在print 之前 return

Python：这个函数出了什么问题？

2 个答案: