Question

我正在尝试打印列表，删除项目0，然后为列表中的所有项目再次打印列表。这很简单，但是没有按我预期的那样工作。它没有完成所有列表项的for循环。

我首先尝试同时在del和pop（）方法中使用列表中的range函数。那没有用，所以我一直在使用列表并获得相同的结果。

seals = [1,2,3,4,5,6,7,8,9]

for seal in seals:
    print(seals)
    seals.pop(0)

Expected Result
[1, 2, 3, 4, 5, 6, 7, 8, 9]
[2, 3, 4, 5, 6, 7, 8, 9]
[3, 4, 5, 6, 7, 8, 9]
[4, 5, 6, 7, 8, 9]
[5, 6, 7, 8, 9]
[6, 7, 8, 9]
[7, 8, 9]
[8, 9]
[9]

Actual Result
[1, 2, 3, 4, 5, 6, 7, 8, 9]
[2, 3, 4, 5, 6, 7, 8, 9]
[3, 4, 5, 6, 7, 8, 9]
[4, 5, 6, 7, 8, 9]
[5, 6, 7, 8, 9]

Answer 1

Python在这里很有趣，所以您必须对他很清楚：D：

seals = [1,2,3,4,5,6,7,8,9]

for seal in seals[:]:
    print(seals)
    seals.pop(0)

或使用range：

seals = [1,2,3,4,5,6,7,8,9]

for seal in range(len(seals)):
    print(seals)
    seals.pop(0)

两者均重现：

[1, 2, 3, 4, 5, 6, 7, 8, 9]
[2, 3, 4, 5, 6, 7, 8, 9]
[3, 4, 5, 6, 7, 8, 9]
[4, 5, 6, 7, 8, 9]
[5, 6, 7, 8, 9]
[6, 7, 8, 9]
[7, 8, 9]
[8, 9]
[9]

Answer 2

如果您打算pop贬值直到没有其他值，则可以使用以下类似的代码将其写入代码中可能更清楚：

seals = [1,2,3,4,5,6,7,8,9]

while seals:
    print(seals)
    seals.pop(0)

这避免了在迭代相同列表时修改列表的问题。

如果您不想随便修改印章，则可以执行以下操作：

seals = [1,2,3,4,5,6,7,8,9]

for i, v in enumerate(seals):
    print(seals[i:])

seals在此结束时保持不变。

具有数字列表的Python for循环无法正常工作

2 个答案: