You are given an array of k linked-lists lists, each linked-list is sorted in ascending order.
Merge all the linked-lists into one sorted linked-list and return it.
Example 1:
Input: lists = [[1,4,5],[1,3,4],[2,6]]
Output: [1,1,2,3,4,4,5,6]
Explanation: The linked-lists are:
[
1->4->5,
1->3->4,
2->6
]
merging them into one sorted list:
1->1->2->3->4->4->5->6
Example 2:
Input: lists = []
Output: []
Example 3:
Input: lists = [[]]
Output: []
public static ListNode mergeKLists(ListNode[] lists){
return partion(lists,0,lists.length-1);
}
public static ListNode partion(ListNode[] lists,int s,int e){
if(s==e) return lists[s];
if(s<e){
int q=(s+e)/2;
ListNode l1=partion(lists,s,q);
ListNode l2=partion(lists,q+1,e);
return merge(l1,l2);
}else
return null;
}
public static ListNode merge(ListNode l1,ListNode l2){
if(l1==null) return l2;
if(l2==null) return l1;
if(l1.val<l2.val){
l1.next=merge(l1.next,l2);
return l1;
}else{
l2.next=merge(l1,l2.next);
return l2;
}
}