{ "data": { "question": { "questionId": "2216", "questionFrontendId": "2095", "boundTopicId": null, "title": "Delete the Middle Node of a Linked List", "titleSlug": "delete-the-middle-node-of-a-linked-list", "content": "
You are given the head
of a linked list. Delete the middle node, and return the head
of the modified linked list.
The middle node of a linked list of size n
is the ⌊n / 2⌋th
node from the start using 0-based indexing, where ⌊x⌋
denotes the largest integer less than or equal to x
.
n
= 1
, 2
, 3
, 4
, and 5
, the middle nodes are 0
, 1
, 1
, 2
, and 2
, respectively.\n
Example 1:
\n\n\nInput: head = [1,3,4,7,1,2,6]\nOutput: [1,3,4,1,2,6]\nExplanation:\nThe above figure represents the given linked list. The indices of the nodes are written below.\nSince n = 7, node 3 with value 7 is the middle node, which is marked in red.\nWe return the new list after removing this node. \n\n\n
Example 2:
\n\n\nInput: head = [1,2,3,4]\nOutput: [1,2,4]\nExplanation:\nThe above figure represents the given linked list.\nFor n = 4, node 2 with value 3 is the middle node, which is marked in red.\n\n\n
Example 3:
\n\n\nInput: head = [2,1]\nOutput: [2]\nExplanation:\nThe above figure represents the given linked list.\nFor n = 2, node 1 with value 1 is the middle node, which is marked in red.\nNode 0 with value 2 is the only node remaining after removing node 1.\n\n
\n
Constraints:
\n\n[1, 105]
.1 <= Node.val <= 105
Compiled with clang 11
using the latest C++ 17 standard.
Your code is compiled with level two optimization (-O2
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Most standard library headers are already included automatically for your convenience.
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\\r\\n\\r\\nFor hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:
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Go 1.17.6
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