Merge Two Sorted Lists Show result

Merge two sorted (ascending) linked lists and return it as a new sorted list. The new sorted list should be made by splicing together the nodes of the two lists and sorted in ascending order.

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Yes

Example

Given 1->3->8->11->15->null, 2->null , return1->2->3->8->11->15->null.

/**

 * Definition for ListNode.

 * public class ListNode {

 *     int val;

 *     ListNode next;

 *     ListNode(int val) {

 *         this.val = val;

 *         this.next = null;

 *     }

 * }

 */ 

public class Solution {

    /**

     * @param ListNode l1 is the head of the linked list

     * @param ListNode l2 is the head of the linked list

     * @return: ListNode head of linked list

     */

    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {

        // write your code here

        

        ListNode dummy = new ListNode(0);

        ListNode node = dummy;

        while(l1 != null && l2 != null){

            if(l1.val < l2.val){

                node.next = l1;

                l1 = l1.next;

            } else{

                node.next = l2;

                l2 = l2.next;

            }

            node = node.next;

        }

        if(l1 != null) node.next = l1;

        if(l2 != null) node.next = l2;

        return dummy.next;

    }

}