Create a Circular Singly Linked List in DSA C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a node structure for a circular singly linked list.

DSA C

struct Node {
    int data;
    struct Node* [1];
};

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

Aprev

Bnext

Cchild

Dlink

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'prev' which is for doubly linked lists.

Using 'child' or 'link' which are not standard names here.

The pointer to the next node in a singly linked list is commonly named 'next'.

2fill in blank

medium

Complete the code to create a new node and assign data to it.

DSA C

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

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ANULL

Bvalue

C0

Ddata

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning NULL or 0 instead of the actual data.

Using an undefined variable like 'value'.

We assign the input 'data' value to the new node's data field.

3fill in blank

hard

Fix the error in linking the new node to itself for a single-node circular list.

DSA C

newNode->next = [1];

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ANULL

Bhead

CnewNode

Dtemp

Attempts:

3 left

💡 Hint

Common Mistakes

Setting next to NULL breaks the circular property.

Using 'head' or 'temp' without initialization.

For a single-node circular list, the node's next pointer should point to itself.

4fill in blank

hard

Fill both blanks to insert a new node at the end of a circular singly linked list.

DSA C

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

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

Anext

Bprev

Clink

Dchild

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'prev' which is for doubly linked lists.

Using different pointer names in the loop causing errors.

To traverse the circular list, we follow the 'next' pointers until we reach the head again.

5fill in blank

hard

Fill all three blanks to create a function that inserts a node at the end of a circular singly linked list.

DSA C

void insertEnd(struct Node** head, int data) {
    struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
    newNode->data = [1];
    if (*head == NULL) {
        newNode->next = [2];
        *head = newNode;
    } else {
        struct Node* temp = *head;
        while (temp->next != *head) {
            temp = temp->next;
        }
        temp->next = newNode;
        newNode->next = [3];
    }
}

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

Adata

BnewNode

C*head

DNULL

Attempts:

3 left

💡 Hint

Common Mistakes

Not setting newNode->next correctly for empty list.

Linking newNode->next to NULL instead of head.

We assign 'data' to newNode->data, point newNode->next to itself if list is empty, and link newNode->next to head otherwise.