列表推导式|Python技能树征题

• 第一题（难度：⭐⭐⭐⭐）
• 第二题
• 第三题

坤坤想要找到20以内的所有质数，他写了下面四段程序，哪些能够正确输出结果呢？
A.

arr = [i for i in range(1, 20) for j in range(1, 20) if j % i == 0 and j > i]
print(arr)

B.

arr = {j for i in range(2, 20) for j in range(i + 1, 20) if j % i == 0}
arr = [i for i in range(2, 20) if i not in arr]
print(arr)

C.

arr = {j for i in range(2, 20) for j in range(i, 20) if j % i == 0}
arr = [i for i in range(2, 20) if i not in arr]
print(arr)

D.

arr = {j for i in range(1, 20) for j in range(i + 1, 20) if j % i == 0}
arr = [i for i in range(2, 20) if i not in arr]
print(arr)

正确答案：B

坤坤有两个数列s1和s2如下所示。

s1 = [i for i in range(100) if i % 2 == 0]
s2 = [i for i in range(100) if i % 3 == 0]

现在他想找到所有只出现在s2而没有出现在s1中的数字，下列代码段中不能够达到相同效果或无法运行的是。
A.

a = [i for i in s2 if i not in s1]

B.

b = [i for i in s2 if i & 1]

C.

c = [i for i in s2 for i not in s1]

D.

d = [i for i in s2 if i not in [i for i in s1 if i in s2]]

正确答案：C

下列语句没有语法错误的是
A.

a = [i + j for i in [0, 1] and for j in [0, 1]]

B.

b = [i if i < 10 for i in range(20)]

C.

c = {i: j for i in range(10) for j in [1, 2]}

D.

d = {j - 1 for i in {i + 1 for j in {0 for _ in range(10)}}}

正确答案：C