Create LinkedList-kReverse

Author: mmuskan22

LinkedList-kReverse

@@ -0,0 +1,90 @@
+Given a singly linked list of integers, reverse the nodes of the linked list 'k' at a time and return its modified list.
+ 'k' is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of 'k,' then left-out nodes, in the end, should be reversed as well.
+Example :
+Given this linked list: 1 -> 2 -> 3 -> 4 -> 5
+
+For k = 2, you should return: 2 -> 1 -> 4 -> 3 -> 5
+
+For k = 3, you should return: 3 -> 2 -> 1 -> 5 -> 4
+ Note :
+No need to print the list, it has already been taken care. Only return the new head to the list.
+ Input format :
+The first line contains an Integer 't' which denotes the number of test cases or queries to be run. Then the test cases follow.
+
+The first line of each test case or query contains the elements of the singly linked list separated by a single space.
+
+The second line of input contains a single integer depicting the value of 'k'.
+ Remember/Consider :
+While specifying the list elements for input, -1 indicates the end of the singly linked list and hence, would never be a list element
+Output format :
+For each test case/query, print the elements of the updated singly linked list.
+
+Output for every test case will be printed in a separate line.
+Constraints :
+1 <= t <= 10^2
+0 <= M <= 10^5
+Where M is the size of the singly linked list.
+0 <= k <= M
+
+Time Limit:  1sec
+Sample Input 1 :
+1
+1 2 3 4 5 6 7 8 9 10 -1
+4
+Sample Output 1 :
+4 3 2 1 8 7 6 5 10 9
+Sample Input 2 :
+2
+1 2 3 4 5 -1
+0
+10 20 30 40 -1
+4
+Sample Output 2 :
+1 2 3 4 5 
+40 30 20 10 
+
+*****************************************Code***************************************
+public class Solution {
+
+	public static LinkedListNode<Integer> kReverse(LinkedListNode<Integer> head, int k) {
+		
+        if(head==null || head.next==null)
+            return head;
+        if(k==0)
+            return head;
+        LinkedListNode<Integer> temp=head,h1=head,h2;
+        int cnt=1;
+        while(cnt<k && temp.next!=null)
+        {
+            temp=temp.next;
+            cnt++;
+        }
+        h2=temp.next;
+        temp.next=null;
+        DoubleNode ans=reverse(h1);
+        LinkedListNode<Integer> head2=kReverse(h2,k);
+        ans.tail.next=head2;
+        return ans.head;
+	}
+    private static DoubleNode reverse(LinkedListNode<Integer> head)
+    {
+        if(head==null || head.next==null)
+        {
+            DoubleNode ans=new DoubleNode();
+            ans.head=head;
+            ans.tail=head;
+            return ans;
+        }
+        DoubleNode ans=reverse(head.next);
+        ans.tail.next=head;
+        head.next=null;
+        ans.tail=ans.tail.next;
+        return ans;
+    }
+}
+    class DoubleNode
+    {
+        LinkedListNode<Integer> head;
+        LinkedListNode<Integer> tail;
+    }
+