Delete Node at End in DSA C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to move to the last node in the linked list.

DSA C

while (temp->[1] != NULL) {
    temp = temp->next;
}

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

Ahead

Bdata

Cprev

Dnext

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'prev' instead of 'next' to move forward.

Trying to access 'data' pointer which does not link nodes.

To traverse a linked list, we move from the current node to the next node using the 'next' pointer until we reach the last node where next is NULL.

2fill in blank

medium

Complete the code to update the second last node's next pointer to NULL after deleting the last node.

DSA C

prev->[1] = NULL;

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

Anext

Bdata

Cprev

Dhead

Attempts:

3 left

💡 Hint

Common Mistakes

Setting 'data' to NULL instead of 'next'.

Trying to set 'prev' pointer which is not used here.

To remove the last node, the second last node's 'next' pointer must be set to NULL to mark the new end of the list.

3fill in blank

hard

Fix the error in the code to correctly free the last node after deletion.

DSA C

free([1]);

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

Ahead

Btemp

Cprev

Dnext

Attempts:

3 left

💡 Hint

Common Mistakes

Freeing 'prev' which points to the second last node.

Freeing 'head' which is the start of the list.

The pointer 'temp' points to the last node that needs to be deleted, so we free 'temp' to release its memory.

4fill in blank

hard

Fill both blanks to traverse the list and keep track of the previous node.

DSA C

while (temp->next != NULL) {
    [1] = temp;
    temp = temp->[2];
}

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

Aprev

Btemp

Cnext

Dhead

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping 'prev' and 'temp' assignments.

Using 'temp' instead of 'next' to move forward.

We assign 'prev' to current 'temp' before moving 'temp' to the next node to keep track of the node before the last.

5fill in blank

hard

Fill all three blanks to handle the case when the list has only one node and delete it.

DSA C

if (head->next == NULL) {
    free([1]);
    [2] = NULL;
    return [3];
}

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

Ahead

Btemp

CNULL

Attempts:

3 left

💡 Hint

Common Mistakes

Freeing 'temp' which may not be initialized here.

Returning NULL literal instead of 'head' pointer.

If only one node exists, free 'head', set 'head' to NULL, and return the updated 'head' pointer.