我不明白为什么要分配给下面每个列表中的第一个元素:
➜ ~ python
Python 2.7.3 (default, Sep 26 2012, 21:53:58)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> board = [[None]*5]*5
>>> print board
[[None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None]]
>>> board[0][0] = 1
>>> print board
[[1, None, None, None, None], [1, None, None, None, None], [1, None, None, None, None], [1, None, None, None, None], [1, None, None, None, None]]
我希望最终输出为:
[[1, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None]]
答案 0 :(得分:1)
您的代码与此代码相同:
x = [None]*5
board = [x for i in range(5)]
如果您想要5个不同的列表,请执行以下操作:
board = [[None]*5 for i in range(5)]