Swapping Nodes in a Linked List

 https://leetcode.com/problems/swapping-nodes-in-a-linked-list/


class Solution {
public:
    ListNode* swapNodes(ListNode* head, int k) {
        ListNode* p1=head;
        ListNode* p2=head;
        ListNode* kth=NULL;
        while(--k){
            p1=p1->next;
        }
        kth=p1;
        p1=p1->next;
        while(p1){
            p1=p1->next;
            p2=p2->next;
        }
        swap(kth->val,p2->val);
        
        return head;
    }
};

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