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    Question

    Which of the following operations is most efficient in a

    singly linked list compared to an array?
    A Accessing the middle element Correct Answer Incorrect Answer
    B Deleting the first element Correct Answer Incorrect Answer
    C Accessing the last element Correct Answer Incorrect Answer
    D Inserting an element at a specific position Correct Answer Incorrect Answer
    E Searching for an element Correct Answer Incorrect Answer

    Solution

    In a singly linked list, deleting the first element is very efficient and takes O(1) time. This is because the head pointer of the linked list can directly reference the next node, bypassing the first node. No traversal or shifting of elements is required, unlike an array, where deletion involves shifting all subsequent elements, making it O(n) The pointer manipulation in a linked list ensures this operation is constant time, making it highly advantageous over arrays for scenarios involving frequent deletion of the first element.   Why Other Options Are Incorrect ·         Option 1 (Accessing the middle element): In a singly linked list, accessing any element requires traversing from the head node to the desired position, making it O(n) In contrast, an array supports direct access using an index, making it O(1) ·         Option 3 (Accessing the last element): Accessing the last element in a singly linked list requires traversing through all nodes from the head, making it O(n) In an array, accessing the last element is an O(1) operation because the index of the last element is directly available. ·         Option 4 (Inserting an element at a specific position): To insert at a specific position, a singly linked list requires traversal up to that position, which is O(n) In an array, insertion requires shifting elements, also O(n), but for specific use cases, arrays might be preferable for direct indexing. ·         Option 5 (Searching for an element): Searching is linear in a singly linked list (O(n) , as each node must be checked. In arrays, searching can also be O(n) , but if the array is sorted, binary search can reduce complexity to O(log ⁡ n)

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