Check if an array contains any element of another array in Python

Question

a = [1, 2, 3]
b = [4, 5, 1]

I need to check if one (or more) elements are common in both arrays.

U13-Forward · Accepted Answer · 2021-10-05T05:28:59.120

5

Check the intersections of the sets and get the boolean:

>>> bool(set(a) & set(b))
True
>>>

Or not not:

>>> not not (set(a) & set(b))
True
>>>

Or just with any:

>>> any(i in b for i in a)
True
>>>

edited Oct 05 '21 at 05:28

answered Oct 05 '21 at 05:22

U13-Forward

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The `not not` seems ridiculous when you can just convert it to a bool. – rkechols Oct 05 '21 at 06:03
@rkechols Actually it's faster than `bool` :) – U13-Forward Oct 05 '21 at 06:03
@rkechols Check [this](https://stackoverflow.com/questions/25594231/why-is-not-faster-than-bool-in-python-or-speed-of-python-functions-vs-s) out. – U13-Forward Oct 05 '21 at 06:04
But it obscures the purpose of the code. If you're going for speed, you shouldn't be using python. – rkechols Oct 05 '21 at 06:04
@rkechols yeah, that's true – U13-Forward Oct 05 '21 at 06:05

score 0 · Answer 2 · answered Oct 05 '21 at 05:28

this is simple intersection concept which we used to learn in maths well here I have tried to demonstrate the function which take common from two list and return new list with common elements

    def intersection(lst1, lst2):
        lst3 = [value for value in lst1 if value in lst2]
        return lst3
    
    
    a = [1, 2, 3]
    b = [4, 5, 1]
    
    print(intersection(a,b))

Check if an array contains any element of another array in Python

2 Answers2