Two linked lists L1 (9 nodes) and L2 (7 nodes) are given. The following C code segment modifies L1 b

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Question

Two linked lists L1 (9 nodes) and L2 (7 nodes) are given. The following C code segment modifies L1 by removing nodes whose data value exists in L2. The number of nodes in L1 after execution is ______.

Accepted Answer

Answer: 5Concept — Linked List Node Deletion: The code traverses L1 and removes any node (starting from the second node) whose data value is found in L2. The find() function checks if a given value exists anywhere in L2.Algorithm analysis:ptr1 starts at L1 (head). The loop condition is ptr1->next != NULL.At each step, it checks if ptr1->next->data exists in L2 using find().If yes: ptr1->next = ptr1->next->next (remove the next node, ptr1 stays).If no: ptr1 = ptr1->next (advance ptr1).Key observation: The first node (head) of L1 is never directly checked — only ptr1->next is examined. So even if the head's data exists in L2, it would not be removed by this code. Starting from the second node, any node with data found in L2 is deleted.Based on the specific data values in L1 and L2 as given in the GATE 2025 exam figure: 4 nodes from L1 (nodes 2 through 9) have their data values present in L2 and are removed. The head node and 4 other nodes remain, giving a total of 5 nodes in L1 after execution.

Two linked lists L1 (9 nodes) and L2 (7 nodes) are given. The following C code segment modifies L1 by removing nodes whose data value exists in L2. The number of nodes in L1 after execution is ______.

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Two linked lists L1 (9 nodes) and L2 (7 nodes) are given. The following C code segment modifies L1 by removing nodes whose data value exists in L2. The number of nodes in L1 after execution is ______.

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