Description: Merge two sorted linked lists into a new sorted linked list and return it. The new linked list is formed by splicing all the nodes of the given two linked lists.
eg:
Input: 1->2->4, 1->3->4 Output: 1->1->2->3->4->4
def mergeTwoLists(self, l1, l2):
"""
:type l1: ListNode
:type l2: ListNode
:rtype: ListNode
"""
mylist=listnow=ListNode(0)
while l1 and l2:
if l1.val<l2.val:
listnow.next=l1
l1=l1.next
else:
listnow.next=l2
l2=l2.next
listnow=listnow.next
listnow.next=l1 or l2
return mylist.next