python two-dimensional array assignment initialize

#if you want to initialize a 9*9 two-dimensional array 

[([""]*9) for i in range(9)]

#caution:  the follow code can‘t work
[[""]*9]*9

shallow copies of list concatenated 

if you change one row then the prefix row will also be changed

时间： 2024-12-08 04:57:57

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