<p>Given the <code>head</code> of a linked list, return <em>the list after sorting it in <strong>ascending order</strong></em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/14/sort_list_1.jpg" style="width: 450px; height: 194px;" />
<pre>
<strong>Input:</strong> head = [4,2,1,3]
<strong>Output:</strong> [1,2,3,4]
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/14/sort_list_2.jpg" style="width: 550px; height: 184px;" />
<pre>
<strong>Input:</strong> head = [-1,5,3,4,0]
<strong>Output:</strong> [-1,0,3,4,5]
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> head = []
<strong>Output:</strong> []
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li>The number of nodes in the list is in the range <code>[0, 5 * 10<sup>4</sup>]</code>.</li>
	<li><code>-10<sup>5</sup> &lt;= Node.val &lt;= 10<sup>5</sup></code></li>
</ul>

<p>&nbsp;</p>
<p><strong>Follow up:</strong> Can you sort the linked list in <code>O(n logn)</code> time and <code>O(1)</code> memory (i.e. constant space)?</p>

class Solution {
public:
    ListNode* sortList(ListNode* head) {
        if (head == nullptr) {
            return nullptr;
        }
        if (head->next == nullptr) {
            return head;
        }

        // Extract the elements from the linked list
        std::vector<int> elements;
        ListNode* current = head;
        while (current != nullptr) {
            elements.push_back(current->val);
            current = current->next;
        }

        // Sort the elements
        std::sort(elements.begin(), elements.end());

        // Create a new sorted linked list
        ListNode* result = new ListNode(elements[0]);
        ListNode* resultPointer = result;
        for (size_t i = 1; i < elements.size(); ++i) {
            resultPointer->next = new ListNode(elements[i]);
            resultPointer = resultPointer->next;
        }

        return result;
    }
};
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