. Merge k Sorted Lists

Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.

AC Code:

defMergeklists_merge_sort (self, lists):defmerge (Lst1, lst2): Dummy= PT = ListNode (-1)             whileLst1 andLst2:ifLst1.val <Lst2.val:pt.next=Lst1 Lst1=Lst1.nextElse: Pt.next=Lst2 Lst2=Lst2.next PT=Pt.next Pt.next= Lst1if  notLst2ElseLst2returnDummy.nextif  notlists:returnNoneifLen (lists) = = 1:            returnLists[0] Mid= Len (lists)/2 Left=Self.mergeklists_merge_sort (Lists[:mid]) right=Self.mergeklists_merge_sort (lists[mid:])returnMerge (left, right)

Start with recursion and find out the timeout. Later borrowed from the online code, using the merge sort.

In addition, there are methods such as priority queuing, which are supplemented later.

. Merge k Sorted Lists