LeetCode #21 Merge Two Sorted Lists (E)

[Problem]

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.

 

[Analysis]

没什么好说的，就是按序visit并把两个list的node接在一起。

 

[Solution]

public class Solution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {        
        ListNode mergedHead = new ListNode(0);                    
        ListNode node = mergedHead;
        
        while (l1 != null && l2 != null) {                        
            if (l1.val > l2.val) {
                node.next = l2;
                node = node.next;
                l2 = l2.next;
            } else {
                node.next = l1;
                node = node.next;
                l1 = l1.next;
            }
        }        
        node.next = l1 == null? l2 : l1;        
        
        return mergedHead.next;                    
    }
}