how to maintain the order of elements in a list?

Question

I am performing a list operation as below in python ,it works fine but the order of elements get sorted ,ideally I want the elements order in LISTC to be the same as in LISTA removing the elements from LISTB?how can I do that?

LISTC = list(set(LISTA) - set(LISTB))

http://stackoverflow.com/questions/9792664/set-changes-element-order — Random Davis, May 19 '16 at 18:06
Possible Duplicate of [Get difference between two lists](http://stackoverflow.com/q/3462143)? (see the second answer) — Bhargav Rao, May 19 '16 at 18:12

score 0 · Accepted Answer · answered May 19 '16 at 18:07

0

Stop removing the order from your types.

LISTC = [el for el in LISTA if el not in set(LISTB)]

answered May 19 '16 at 18:07

Ignacio Vazquez-Abrams

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You should create `set(LISTB)` outside the comprehension. Creating it inside the comprehension recreates it on every iteration, defeating the benefit of using a set in the first place. – user2357112 May 19 '16 at 18:10

how to maintain the order of elements in a list?

1 Answers1