how to get INDEX of each values in LIST which are SAME

Question

let a list, a=[20,40,50,20,80]
then p=[a.index(x) for x in a if x==20]
output of p will be
[0,0]
but i wanted the output as [0, 3]
why it is so

Answer 1

Hi Rakesh!
Hope you know that index() will give the first occurrence of an item in a list.
print(a.index(20))

Inorder to handle this problem, you can use enumerate() method.
So, your code needs to be like this

a=[20,40,50,20,80]
p=[x for x,y in enumerate(a) if y==20]
print(p)

output: [0,3]

Answer 2

Thank you.. I got your answer..