Insert at End of Doubly Linked List in DSA C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new node with given data.

DSA C

struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
newNode->data = [1];
newNode->next = NULL;
newNode->prev = NULL;

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

Adata

BNULL

Chead

Dtemp

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning NULL or other pointers instead of the data value.

Forgetting to assign the data field.

The new node's data field should be set to the given data value.

2fill in blank

medium

Complete the code to check if the list is empty.

DSA C

if (*head == [1]) {
    *head = newNode;
    return;
}

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Atemp

BNULL

Chead

DnewNode

Attempts:

3 left

💡 Hint

Common Mistakes

Comparing head to newNode or other pointers.

Using assignment '=' instead of comparison '=='.

If *head is NULL, the list is empty and the new node becomes the head.

3fill in blank

hard

Fix the error in the loop that finds the last node.

DSA C

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

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Aprev

Bdata

Cnext

Dhead

Attempts:

3 left

💡 Hint

Common Mistakes

Using temp->prev which moves backward.

Checking temp->data instead of pointers.

To find the last node, traverse while temp->next is not NULL.

4fill in blank

hard

Fill both blanks to link the new node at the end.

DSA C

temp->next = [1];
[2]->prev = temp;

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AnewNode

Bhead

Ctemp

DNULL

Attempts:

3 left

💡 Hint

Common Mistakes

Linking to head or temp incorrectly.

Not updating both next and prev pointers.

The last node's next points to newNode, and newNode's prev points back to last node.

5fill in blank

hard

Fill all three blanks to complete the insert at end function.

DSA C

void insertEnd(struct Node** head, int data) {
    struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
    newNode->data = [1];
    newNode->next = NULL;
    newNode->prev = NULL;

    if (*head == [2]) {
        *head = newNode;
        return;
    }

    struct Node* temp = *head;
    while (temp->next != NULL) {
        temp = temp->next;
    }

    temp->next = [3];
    newNode->prev = temp;
}

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

Adata

BNULL

CnewNode

Dhead

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to dereference head pointer.

Linking temp->next to wrong node.

Not setting newNode->prev correctly.

Assign data to newNode->data, check if *head is NULL, and link temp->next to newNode.