merge k sorted lists

Author: se6816

merge-k-sorted-lists/se6816.java

@@ -0,0 +1,28 @@
+
+class Solution {
+    public ListNode mergeKLists(ListNode[] lists) {
+            ListNode list= new ListNode(0); // head
+            ListNode curr=list;
+            PriorityQueue<ListNode> pq=new PriorityQueue<ListNode>((l1, l2)->{
+                return l1.val - l2.val;
+            });
+            for(int i=0; i<lists.length;i++){
+                if(lists[i]!=null){
+                    pq.offer(lists[i]);
+                }
+            }
+            while(!pq.isEmpty()){
+                ListNode temp = pq.poll();
+                curr.next=new ListNode(temp.val);
+                curr=curr.next;
+                temp=temp.next;
+                if(temp!=null){
+                    pq.offer(temp);
+                }
+
+            }
+            return list.next;
+                
+        
+    }
+}