Is in python 2.7.10 '[[]]*2' different than ' [[],[]] ' ? Aren't they both same?

Asked Jun 17 '16 at 21:55

Active Jun 17 '16 at 22:59

Viewed 46 times

I was solving a problem using python2 and I used 'seq= [[]]*2' because I wanted this '[[],[]]. But I got wrong answer. Then I tested it in IDLE like this:

>>>s=[[],[]]
>>>seq=[[]]*2
>>>seq
[[], []]
>>>s[0].append(5)
>>>s
[[5],[]]
>>>seq[0].append(5)
>>>seq
[[5],[5]]

I am totally confused. Can anyone help me? Please.

edited Jun 17 '16 at 22:59

asked Jun 17 '16 at 21:55

Salman Lari

1

the test `[[]]*2 == [[],[]]` is True when I tested it, are you sure that is the code you tried? – Tadhg McDonald-Jensen Jun 17 '16 at 22:01
@TadhgMcDonald-Jensen : Actually brother, when I did this 'seq=[[],[]]' and then did this 'seq[0].append(5)', the value of 'seq' became [[5],[]]. But when I did this, 'seq=[[]]*2' and then did 'seq[0].append(5)', then the value of 'seq' became [[5],[5]]. This is haunting me. – Salman Lari Jun 17 '16 at 22:56
1

ok in that case yes this is a duplicate of the one posted. – Tadhg McDonald-Jensen Jun 17 '16 at 22:56
Yeah...Sorry about that. – Salman Lari Jun 17 '16 at 23:01

Is in python 2.7.10 '[[]]*2' different than ' [[],[]] ' ? Aren't they both same?

0 Answers0