Comparing two list and getting result a list with some checks

Question

I have two list a and b I have to get result of two list one with elements which are in both and one in which elements of b which aren't present in a.I have to write the code in python.output and should look like this.

    a = ['product','shampoo','vivel','spark']
    b = ['random','product','shampoo','nothing']
    c = ['product','shampoo']
    d = ['random','nothing']

I need an efficient one as I have to do this some process many times Thank you, please let me know if there is any unclarity.

What's your question? Note: "how do I do this assignment?" is too broad. — Kevin, Jun 02 '16 at 14:28

score 4 · Answer 1 · answered Jun 02 '16 at 14:20

You can use set operations, since that is essentially what you're after.

>>> a = ['product','shampoo','vivel','spark']
>>> b = ['random','product','shampoo','nothing']

The list c would be the result of a set intersection

>>> c = set(a).intersection(b)
>>> c
{'shampoo', 'product'}

The list d would be the result of a set difference of a from b.

>>> d = set(b).difference(a)
>>> d
{'random', 'nothing'}

There are operators for sets that perform these operations as well

>>> set(a) & set(b)
{'shampoo', 'product'}
>>> set(b) - set(a)
{'random', 'nothing'}

score 1 · Accepted Answer · answered Jun 02 '16 at 14:21

An efficient way to perform this task consists of using set -

a = ['product','shampoo','vivel','spark']
b = ['random','product','shampoo','nothing']

c = list(set(a) & set(b))

d = list(set(b) - set(a))

print(c)

print(d)

Output -

['product', 'shampoo']
['nothing', 'random']

Comparing two list and getting result a list with some checks

2 Answers2