创建两个包含 10 个实例的列表，然后创建第三个包含 x 和 y 10 次的列表

Question

有人向我提出问题，但我不太明白他们要我做什么。他们给我的问题是：

本练习的目标是创建两个名为

x_list

和

y_list

的列表，其中分别包含变量

x

和

y

的 10 个实例。您还需要通过连接您创建的两个列表来创建一个名为

big_list

的列表，其中包含变量

x

和

y

，各 10 次。

随之而来的代码是：

x = object()
y = object()

# change this code
x_list = [x]
y_list = [y]
big_list = x_list + y_list

print "x_list contains %d objects" % len(x_list)
print "y_list contains %d objects" % len(y_list)
print "big_list contains %d objects" % len(big_list)

# testing code
if x_list.count(x) == 10 and y_list.count(y) == 10:
    print "Almost there..."
if big_list.count(x) == 10 and big_list.count(y) == 10:
    print "Great!"

结果是：

x_list contains 10 objects
y_list contains 10 objects
big_list contains 20 objects

Almost there...
Great!

Answer 1

要获取多个实例，只需将列表相乘即可：

x_list = [x]*10
y_list = [y]*10

Answer 2

x = object()
y = object()

# TODO: change this code
x_list = [x]*10
y_list = [y]*10
big_list = []

z = x_list + y_list
big_list.append(z)


print("x_list contains %d objects" % len(x_list))
print("y_list contains %d objects" % len(y_list))
print("big_list contains %d objects" % len(big_list))

# testing code
if x_list.count(x) == 10 and y_list.count(y) == 10:
    print("Almost there...")
if big_list.count(x) == 10 and big_list.count(y) == 10:
    print("Great!")

Answer 3

要制作 10 个实例，我们只需将其与

10

相乘，然后在

x_list

中添加

y_list

和

big_list

。

代码：

x = object()
y = object()

# TODO: change this code
x_list = [x]*10
y_list = [y]*10
big_list = x_list + y_list

print("x_list contains %d objects" % len(x_list))
print("y_list contains %d objects" % len(y_list))
print("big_list contains %d objects" % len(big_list))

# testing code
if x_list.count(x) == 10 and y_list.count(y) == 10:
    print("Almost there...")
if big_list.count(x) == 10 and big_list.count(y) == 10:
    print("Great!")

输出：

x_list contains 10 objects
y_list contains 10 objects
big_list contains 20 objects
Almost there...
Great!