I want to insert an element at a specific index in a list and return the updated list

Question

Here is my list:

a = [2, 5, 7, 8, 9]

And I want to insert 3 and 4 after 5 ( at index 2 and 3 repectively)

Answer 1

Hi,

Using insert() method you can insert the elements in given list at required index.

Syntax:

list_name.insert(index, element)

Now coming to your code:

Input:

a = [2, 5, 7, 8, 9]

#element to be inserted

Element = 3 

#element to be inserted before

beforeElement = 7

#find index

index = a.index(beforeElement)  

#insert element at beforeElement 

a.insert(index, Element)  
print(a)

#Similarly to insert 4 after 3 in the list:

Element = 4
beforeElement=7
index= a.index(beforeElement)
a.insert(index, Element)
print(a)

Output:

[2, 5, 3, 4, 7, 8, 9]

As asked above, we have 3 and 4 after 5 in the list as output