Challenge - 5 Problems

🎖️

Circular Linked List Mastery

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Test your skills under time pressure!

🧠 Conceptual

intermediate

2:00remaining

Why use a Circular Linked List instead of a Singly Linked List?

Which of the following is the main advantage of using a circular linked list over a singly linked list?

AIt automatically sorts the elements in ascending order.

BIt uses less memory than a singly linked list because it has no null pointers.

CIt allows easy traversal from any node back to the start without needing to restart from the head.

DIt prevents duplicate values from being inserted.

Attempts:

2 left

❓ Predict Output

intermediate

2:00remaining

Output of Circular Linked List Traversal

What will be the output of the following code that traverses a circular linked list with 3 nodes?

DSA C

struct Node {
    int data;
    struct Node* next;
};

void printList(struct Node* head) {
    struct Node* temp = head;
    if (head != NULL) {
        do {
            printf("%d -> ", temp->data);
            temp = temp->next;
        } while (temp != head);
    }
    printf("null\n");
}

int main() {
    struct Node n1, n2, n3;
    n1.data = 1; n2.data = 2; n3.data = 3;
    n1.next = &n2; n2.next = &n3; n3.next = &n1;
    printList(&n1);
    return 0;
}

A1 -> 2 -> 3 -> null

Bnull

C1 -> 2 -> 3

D1 -> 2 -> 3 -> 1 -> 2 -> 3 -> null

Attempts:

2 left

🚀 Application

advanced

2:00remaining

Real World Use Case of Circular Linked List

Which of the following real-world scenarios is best suited for implementing with a circular linked list?

AA queue where people wait in line and leave after service.

BA phone book where contacts are stored alphabetically.

CA stack of plates where the last added plate is removed first.

DA music playlist that repeats songs continuously in a loop.

Attempts:

2 left

🔧 Debug

advanced

2:00remaining

Identify the Bug in Circular Linked List Insertion

What is the bug in the following code snippet that inserts a new node at the end of a circular linked list?

DSA C

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

AThe while loop condition should be temp->next != NULL instead of temp->next != *head.

BWhen the list is empty, newNode->next should point to newNode itself, not NULL.

CThe newNode->data is not assigned before insertion.

DThe function does not allocate memory for newNode.

Attempts:

2 left

🧠 Conceptual

expert

3:00remaining

Why Circular Linked Lists Are Used in Multiplayer Games

In multiplayer turn-based games, why is a circular linked list often used to manage player turns?

ABecause it allows cycling through players endlessly without resetting or extra checks.

BBecause it sorts players by their scores automatically.

CBecause it uses less memory than arrays for storing players.

DBecause it prevents players from skipping their turns.

Attempts:

2 left