[Tutor] Matrix bug

[Narci Edson Venturini]

The next code has an unexpected result:

>>>a=3*[3*[0]]
>>>a
[[0, 0, 0], [0, 0, 0], [0, 0, 0]]
>>>a[0][0]=1
>>>a
[[1, 0, 0], [1, 0, 0], [1, 0, 0]]

The code assigned to "1" a(0,0), a(1,0) and a(2,0).

It was expected: [[1, 0, 0], [0, 0, 0], [0, 0, 0]]

When the followind code is ran, them the correct result is obtained:

>>>a=[[0 for i in range(3)] for j in range(3)]
>>>>>>a
[[0, 0, 0], [0, 0, 0], [0, 0, 0]]
>>>a[0][0]=1
>>>a
 [[1, 0, 0], [0, 0, 0], [0, 0, 0]]

So, what is wrong ?

Best Regars,



Narci
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Narci Edson Venturini
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