"""Leetcode 21. Merge Two Sorted Lists
Easy

URL: https://leetcode.com/problems/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
"""

# Definition for singly-linked list.
class ListNode(object):
    def __init__(self, val):
        self.val = val
        self.next = None


class Solution(object):
    def mergeTwoLists(self, l1, l2):
        """
        :type l1: ListNode
        :type l2: ListNode
        :rtype: ListNode
        """
        pass


def main():
    pass


if __name__ == '__main__':
    main()

Add lc021_merge_two_sorted_lists.py