<p>You are given the <code>head</code> of a linked list, and an integer <code>k</code>.</p>

<p>Return <em>the head of the linked list after <strong>swapping</strong> the values of the </em><code>k<sup>th</sup></code> <em>node from the beginning and the </em><code>k<sup>th</sup></code> <em>node from the end (the list is <strong>1-indexed</strong>).</em></p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/21/linked1.jpg" style="width: 400px; height: 112px;" />
<pre>
<strong>Input:</strong> head = [1,2,3,4,5], k = 2
<strong>Output:</strong> [1,4,3,2,5]
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> head = [7,9,6,6,7,8,3,0,9,5], k = 5
<strong>Output:</strong> [7,9,6,6,8,7,3,0,9,5]
</pre>

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

<ul>
	<li>The number of nodes in the list is <code>n</code>.</li>
	<li><code>1 &lt;= k &lt;= n &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= Node.val &lt;= 100</code></li>
</ul>


class Solution {
public:
    int size(ListNode* head){
        int count = 0;
        while(head!=NULL){
            head = head->next;
            count++;
        }
        return count;
    }
    ListNode* swapNodes(ListNode* head, int k) {
        int len = size(head);
        vector<int> arr(len);
        ListNode* temp = head;
        int i=0;
        while(temp!=NULL){
            arr[i] = temp->val;
            temp = temp->next;
            i++;
        }
        int tem = arr[k-1];
        arr[k-1] = arr[len-k];
        arr[len-k] = tem;
        temp = head;
        i = 0;
        while(temp!=NULL){
            temp->val = arr[i];
            temp = temp->next;
            i++;
        }
        return head;
    }
};
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