如何在相乘的字符串之间添加空格？

Question

我的代码是这样的：

shopping=["Bread","Butter","Juice"]
for products in shopping:
    print(products * 3 + " ")

其产出是：

breadbread 黄油 果汁指南果汁

我希望我的输出是：

面包 黄油 果汁

Answer 1

尝试以下方法（不是最好的方法，但想展示一下如何用你的方法完成）：

shopping=["Bread","Butter","Juice"]
for products in shopping:
    print((products + " ")* 2 + products)

如果要形成列表，请使用list comprehension和format：

print(["{0} {0} {0}".format(i) for i in shopping])

产出：

['Bread Bread Bread', 'Butter Butter Butter', 'Juice Juice Juice']

或

shopping=["Bread","Butter","Juice"]
for products in shopping:
    print("{0} {0} {0}".format(products))

产出：

Bread Bread Bread
Butter Butter Butter
Juice Juice Juice

Answer 2

不要使用乘法（虽然可用，但很少需要）。相反，请使用' '.join：

print(' '.join([products for _ in range(3)]))

您可以在上面使用list乘法，因为您不关心结果列表的性质，除了它是可iterable之外

print(' '.join([products] * 3))

Answer 3

更简单地说：

shopping=["Bread","Butter","Juice"]
for products in shopping:
    print(products + " ") * 3

输出：

Bread Bread Bread 
Butter Butter Butter 
Juice Juice Juice