Update README.md

README.md

@@ -10,3 +10,92 @@ This tutorial introduces the reader informally to the basic concepts and feature
 For a description of standard objects and modules, see The Python Standard Library. The Python Language Reference gives a more formal definition of the language. To write extensions in C or C++, read Extending and Embedding the Python Interpreter and Python/C API Reference Manual. There are also several books covering Python in depth.
 
 This tutorial does not attempt to be comprehensive and cover every single feature, or even every commonly used feature. Instead, it introduces many of Python’s most noteworthy features, and will give you a good idea of the language’s flavor and style. After reading it, you will be able to read and write Python modules and programs, and you will be ready to learn more about the various Python library modules described in The Python Standard Library.
+# Python program to check binary tree is a subtree of 
+# another tree 
+
+# A binary tree node 
+class Node: 
+
+	# Constructor to create a new node 
+	def __init__(self, data): 
+		self.data = data 
+		self.left = None
+		self.right = None
+
+# A utility function to check whether trees with roots 
+# as root 1 and root2 are indetical or not 
+def areIdentical(root1, root2): 
+
+	# Base Case 
+	if root1 is None and root2 is None: 
+		return True
+	if root1 is None or root2 is None: 
+		return False
+
+	# Check fi the data of both roots is same and data of 
+	# left and right subtrees are also same 
+	return (root1.data == root2.data and
+			areIdentical(root1.left , root2.left)and
+			areIdentical(root1.right, root2.right) 
+			) 
+
+# This function returns True if S is a subtree of T, 
+# otherwise False 
+def isSubtree(T, S): 
+
+	# Base Case 
+	if S is None: 
+		return True
+
+	if T is None: 
+		return False
+
+	# Check the tree with root as current node 
+	if (areIdentical(T, S)): 
+		return True
+
+	# IF the tree with root as current node doesn't match 
+	# then try left and right subtreee one by one 
+	return isSubtree(T.left, S) or isSubtree(T.right, S) 
+
+
+# Driver program to test above function 
+
+""" TREE 1 
+	Construct the following tree 
+			26 
+			/ \ 
+		10	 3 
+		/ \	 \ 
+	4	 6	 3 
+	\ 
+		30 
+	"""
+
+T = Node(26) 
+T.right = Node(3) 
+T.right.right = Node(3) 
+T.left = Node(10) 
+T.left.left = Node(4) 
+T.left.left.right = Node(30) 
+T.left.right = Node(6) 
+
+""" TREE 2 
+	Construct the following tree 
+		10 
+		/ \ 
+	4	 6 
+	\ 
+		30 
+	"""
+S = Node(10) 
+S.right = Node(6) 
+S.left = Node(4) 
+S.left.right = Node(30) 
+
+if isSubtree(T, S): 
+	print "Tree 2 is subtree of Tree 1"
+else : 
+	print "Tree 2 is not a subtree of Tree 1"
+
+# This code is contributed by Nikhil Kumar Singh(nickzuck_007)