edit 156

Author: fishercoder1534

README.md

@@ -391,7 +391,7 @@ Your ideas/fixes/algorithms are more than welcome!
 |159|[Longest Substring with At Most Two Distinct Characters](https://leetcode.com/problems/longest-substring-with-at-most-two-distinct-characters/)|[Solution](../master/src/main/java/com/fishercoder/solutions/LongestSubstringwithAtMostTwoDistinctCharacters.java)| O(n)|O(1) | Hard| String, Sliding Window
 |158|[Read N Characters Given Read4 II - Call multiple times](https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/)|[Solution](../master/src/main/java/com/fishercoder/solutions/ReadNCharactersGivenRead4IICallMultipleTimes.java)| O(n)|O(1) | Hard|
 |157|[Read N Characters Given Read4](https://leetcode.com/problems/read-n-characters-given-read4/)|[Solution](../master/src/main/java/com/fishercoder/solutions/ReadNCharactersGivenRead4.java)| O(n)|O(1) | Easy| 
-|156|[Binary Tree Upside Down](https://leetcode.com/problems/binary-tree-upside-down/)|[Solution](../master/src/main/java/com/fishercoder/solutions/BinaryTreeUpsideDown.java)| O(n)|O(h) | Medium| Tree, Recursion
+|156|[Binary Tree Upside Down](https://leetcode.com/problems/binary-tree-upside-down/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_156.java)| O(n)|O(h) | Medium| Tree, Recursion
 |155|[Min Stack](https://leetcode.com/problems/min-stack/)|[Solution](../master/src/main/java/com/fishercoder/solutions/MinStack.java)| O(1)|O(n) | Easy| Stack
 |154|[Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_154.java)| O(logn)|O(1) | Hard| Array, Binary Search
 |153|[Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_153.java)| O(logn)|O(1) | Medium| Array, Binary Search

src/main/java/com/fishercoder/solutions/BinaryTreeUpsideDown.java src/main/java/com/fishercoder/solutions/_156.java

@@ -3,27 +3,28 @@
 import com.fishercoder.common.classes.TreeNode;
 
 /**
- * Given a binary tree where all the right nodes are either leaf nodes with a sibling (a left node that shares the same parent node) or empty, flip it upside down and turn it into a tree where the original right nodes turned into left leaf nodes. Return the new root.
+ * Given a binary tree where all the right nodes are either leaf nodes with a sibling
+ * (a left node that shares the same parent node) or empty,
+ * flip it upside down and turn it into a tree where the original right nodes turned into left leaf nodes. Return the new root.
 
  For example:
  Given a binary tree {1,2,3,4,5},
-  1
- / \
- 2 3
- /  \
- 4  5
+    1
+   / \
+  2  3
+ /    \
+4     5
  return the root of the binary tree [4,5,2,#,#,3,1].
-  4
- / \
- 5 2
- /  \
- 3  1
+    4
+   / \
+  5  2
+ /    \
+3     1
  confused what "{1,#,2,3}" means? > read more on how binary tree is serialized on OJ.
  */
-public class BinaryTreeUpsideDown {
+public class _156 {
 
-    public TreeNode upsideDownBinaryTree(TreeNode root)
-    {
+    public TreeNode upsideDownBinaryTree(TreeNode root) {
         if (root == null || root.left == null && root.right == null)
             return root;
         TreeNode newRoot = upsideDownBinaryTree(root.left);