<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>


// decalre an array and store the values of LL in the array
// then swap the kth from front and rear
// again set the elements of array to LL

class Solution {
public:
    ListNode* swapNodes(ListNode* head, int k) {
        ListNode* temp= head;
     ListNode* len= head;
     int length = 0;

        while(len!=nullptr){
            len = len->next;
            length ++;
        }

       
        int i=0;
        vector <int > arr(length); // deaclare an array

                while(temp!= nullptr){
            arr[i]= temp->val;
          temp=  temp->next;
            i++;
        }
        int first= k-1;
        int second=  length-k;

        int temp10= arr[second];
        arr[second] = arr[first];
        arr[first]= temp10;
        temp= head;
        int j=0;
        while(j != length)
            {
                temp->val = arr[j];
                temp = temp->next;
                j++;
            }
            return head;
    }};

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