Delete Node by Value in DSA Python - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the linked list is empty before deletion.

DSA Python

if self.head is [1]:
    return

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ANone

B0

CTrue

DFalse

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 or False instead of None to check for empty list.

We check if self.head is None to see if the list is empty.

2fill in blank

medium

Complete the code to delete the head node if it contains the target value.

DSA Python

if self.head.data == [1]:
    self.head = self.head.next
    return

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Anode

Bvalue

Ctarget

Ddata

Attempts:

3 left

💡 Hint

Common Mistakes

Using undefined variable names like 'value' or 'data' instead of 'target'.

The variable target holds the value to delete.

3fill in blank

hard

Fix the error in the while loop condition to traverse the list correctly.

DSA Python

while current is not [1] and current.data != target:
    prev = current
    current = current.next

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ATrue

BFalse

C0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using True or False instead of None in the loop condition.

The loop should continue while current is not None, meaning nodes remain.

4fill in blank

hard

Fill both blanks to correctly remove the node by updating links.

DSA Python

if current is not None:
    [1].next = [2].next

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Aprev

Bcurrent

Cself.head

Dnode

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names or trying to delete the head here.

We set prev.next to skip the current node, effectively deleting it.

5fill in blank

hard

Fill all three blanks to complete the delete_node method.

DSA Python

def delete_node(self, [1]):
    if self.head is None:
        return
    if self.head.data == [2]:
        self.head = self.head.next
        return
    prev = self.head
    current = self.head.next
    while current is not None and current.data != [3]:
        prev = current
        current = current.next
    if current is not None:
        prev.next = current.next

Drag options to blanks, or click blank then click option'

Atarget

Dnode

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing variable names for the target value.

Using undefined variables.

The method parameter is target, the value to delete. We compare self.head.data with target, and in the loop, we compare current.data with target.