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surajr · surajr · commit 346bff90fee1 · 2017-11-04T03:56:17.000-07:00
diff --git a/README.md b/README.md
@@ -148,8 +148,9 @@ Feel free to add issues, create pull requests and be a contributer.
 ## Recursion
 | Website 		| Title           |  Solution    |  Time           | Space           | Difficulty    |  Note| 
 |---------------- |---------------- | ----------- | --------------- | --------------- | ------------- |-----|
-| Leetcode  | [654. Maximum Binary Tree](https://leetcode.com/contest/leetcode-weekly-contest-44/problems/maximum-binary-tree/) | [Java](./java/ConstructMaximumBinaryTree.java)  | _O(n log n)_       | _O(n)_          |  Easy       |         |
 | Leetcode  | [50. Pow(x, n)](https://leetcode.com/problems/powx-n/description/) | [Java](./java/myPow.java)  | _O()_       | _O(n)_          |  Medium       |         |
+| Leetcode  | [654. Maximum Binary Tree](https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/description/) | [Java](./java/sortedListToBST.java)  | _O(n)_       | _O(logn)_          |  Medium       |         |
+| Leetcode  | [654. Maximum Binary Tree](https://leetcode.com/contest/leetcode-weekly-contest-44/problems/maximum-binary-tree/) | [Java](./java/ConstructMaximumBinaryTree.java)  | _O(n log n)_       | _O(n)_          |  Easy       |         |
 
 
 ## Recursion
diff --git a/java/sortedListToBST.java b/java/sortedListToBST.java
@@ -0,0 +1,40 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) { val = x; }
+ * }
+ */
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public TreeNode sortedListToBST(ListNode head) {
+        
+        if(head == null) return null;
+        if(head.next == null)
+            return new TreeNode(head.val);
+        
+        ListNode prev = null, slow = head, fast = head;
+        
+        while(fast != null && fast.next != null)
+        {
+            prev = slow;
+            slow = slow.next;
+            fast = fast.next.next;
+        }
+        prev.next = null;
+        TreeNode root = new TreeNode(slow.val);
+        root.left = sortedListToBST(head);
+        root.right = sortedListToBST(slow.next);
+        
+        return root;       
+    }
+}
