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Leetcode021-mergeTwoSortedLists

Description

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

Example

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Input: 1->2->4, 1->3->4
Output: 1->1->2->3->4->4

Solution

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/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
// More Clean code
if (l1 == null) return l2;
if (l2 == null) return l1;
if (l1.val < l2.val){
l1.next = mergeTwoLists(l1.next, l2);
return l1;
}
else{
l2.next = mergeTwoLists(l1, l2.next);
return l2;
}
}