python - 将元素添加到列表中的特定位置

Question

#Say I have the lists
l1 = [2,3,6,7,9]
l2 = [11,14,16,20,21]

# and a random number, say 8
x = 8

# And I want to change l1 so that if there is any number larger than
# 8 it will be deleted, then 8 will be inserted into the end of l1
#  the output would look like this: [2,3,6,7,8]

# And I want to change l2 so that if there is any number smaller than
# 8 it will be deleted, then 8 will be inserted into the beginning of l2
#  the output would look like this: [8,11,14,16,20,21]

我不确定该怎么做，非常感谢您的帮助。谢谢!

Answer 1

使用列表理解:

l1 = [i for i in l1 if i <= 8]
l1 = l1 + [8]

(或l1.append(8))

和:

l2 = [i for i in l2 if i >= 8]
l2 = [8] + l2

(或 l2.insert(0, 8) 可能更快)