i wanna use append() method in order to appending a temporary list to a empty list using for loop

Asked Sep 22 '21 at 18:24

Active Sep 22 '21 at 18:24

Viewed 15 times

I want to make an list consist on subsequences of another list, for example:

input: array = [4, 1, 8, 2] output that i expect: [[4], [4,1], [4, 1, 8], [4, 1, 8, 2]]

but output is: [[4, 1, 8, 2], [4, 1, 8, 2], [4, 1, 8, 2], [4, 1, 8, 2]]

my code is:

num = [4, 1, 8, 2]
temp = []
sub = []
for item in num:
    temp.append(item)
    sub.append(temp)

append() must add an item to the end of the list, but here every time it adds the temp to the sub it changes the previous items as well, so if it's not a bug please help me to write the correct code.

asked Sep 22 '21 at 18:24

nima

Appending to `sub` does not create a copy of the list, you are still manipulating the same list object. – deceze Sep 22 '21 at 18:29
try this : `sub.append(temp.copy())` – Dhananjay Yadav Sep 23 '21 at 12:29

i wanna use append() method in order to appending a temporary list to a empty list using for loop

0 Answers0