reorganize dir

Signed-off-by: Mia Steinkirch <mia.steinkirch@gmail.com>

ebook_src/trees/check_if_balanced.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python
+
+__author__ = "bt3"
+
+from binary_search_tree import BST, Node
+from binary_tree import BT, Node
+
+
+
+def isBalanced(node, left=0, right=0):
+    if not node:
+        return (left - right) < 2
+
+    return isBalanced(node.left, left+1, right) and \
+        isBalanced(node.right, left, right+1)
+
+
+
+
+if __name__ == '__main__':
+    bt = BST()
+    for i in range(1, 10):
+        bt.add(i)
+
+    assert(isBalanced(bt.root) == True)
+
+    bt = BT()
+    for i in range(1, 10):
+        bt.add(i)
+
+    assert(isBalanced(bt.root) == False)