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Merge Two Sorted Lists - Leetcode 21 - Python

 21. Merge Two Sorted Lists



You are given the heads of two sorted linked lists list1 and list2.


Merge the two lists in a one sorted list. The list should be made by splicing together the nodes of the first two lists.


Return the head of the merged linked list.



class Solution:

    def mergeTwoLists(self, l1: Optional[ListNode], l2: Optional[ListNode]) -> Optional[ListNode]:

        d = ListNode()

        p = d

        

        while l1 and l2 :

            if l1.val < l2.val :

                p.next = l1

                l1 = l1.next

            else :

                p.next = l2

                l2 = l2.next

            p = p.next

                

        if l1:

            p.next = l1

        else :

            p.next = l2

        

        return d.next



Explaination :









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