Deleting an element from a list in Python

Question

I have two lists A and B. I want to delete the element in A from B. I present the current and expected output.

B=[4,5,1]
A=[1]
del B[A[0]]
print(B)

The current output is

[4,1]

The expected output is

[4,5]

Effectively `del B[1]` and you are surprised the element at index 1 is removed!? — luk2302, Dec 31 '22 at 12:43
Try to run this type of small program in the visual platform next time - https://pythontutor.com/ to learn step-by-step ops. — Daniel Hao, Dec 31 '22 at 13:21

score 1 · Accepted Answer · answered Dec 31 '22 at 13:19

As you mention the code, the code will delete an item with index A[0] which is 1. So you can visualize this del B[A[0]] = del B[1] = delete an element which has index 1 in B

Your final code should be:

You can set to do this

B=[4,5,1]
A=[1]

C = set(B) - set(A)

print(list(C))

in this code we are turning list to set and after subtract we will turn the result into list again

or use for loop

 B=[4,5,1]
    A=[1]
    for item in A:
        B.remove(item)
    
    print(B)

here, you can use for loop, it will loop for every item in A and will remove it from B

Deleting an element from a list in Python

1 Answers1