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Unintended output - Nick_Wright - Dec-05-2016
j = [['4', '5'], ['1', '1'], ['1', '5'], ['3', '4'], ['3', '1']] k = [['5', '2'], ['4', '2'], ['2', '4'], ['3', '3'], ['4', '3']] t = [[None] *2] *50 indexPointer = 0 for coord in j: print(coord) for number in coord: t[indexPointer][0] = number indexPointer += 1 indexPointer = 0 for coord in k: for number in coord: t[indexPointer][1] = number indexPointer += 1 print(t)The output is:
[['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3'], ['1', '3']]
The output should be:
[['4','5'],['5','2'],['1','4'],['1','2'],['1','2'],['5','4'],['3','3'],['4','3'],['3','4'],['1','3']]
RE: Unintended output - micseydel - Dec-05-2016
Check out this example of code with a similar issue
>>> t = [[None] *2] *5 >>> t [[None, None], [None, None], [None, None], [None, None], [None, None]] >>> t[0][0] = 1 >>> t [[1, None], [1, None], [1, None], [1, None], [1, None]]