4.merge-two-sorted-lists.md

Merge Two Sorted Lists

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:

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

JavaScript

/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */
/**
 * @param {ListNode} l1
 * @param {ListNode} l2
 * @return {ListNode}
 */
var mergeTwoLists = function (l1, l2) {
    let res = new ListNode();
    let cur = res;
    while (l1 && l2) {
        if (l1.val <= l2.val) {
            cur.next = new ListNode(l1.val);
            l1 = l1.next;
            cur = cur.next;
            continue;
        }
        else {
            cur.next = new ListNode(l2.val);
            l2 = l2.next;
            cur = cur.next;
            continue;
        }
    }
    cur.next = l1 ? l1 : l2;
    return res.next;
};