Merge Two Sorted Lists

Easy

You are given the heads of two sorted linked lists l1 and l2. Splice them into one sorted list and return its head.

Example 1

Input:  l1 = [1,2,4], l2 = [1,3,4]
Output: [1,1,2,3,4,4]

Example 2

Input:  l1 = [], l2 = [0]
Output: [0]

Constraints

• 0 <= list length <= 50
• -100 <= Node.val <= 100
• Both lists are sorted non-decreasing.