Fix #547: Add Binary Search Tree [Python] (#569)

* Create BinarySearchTree.py

* Update BinarySearchTree.py

* Update BinarySearchTree.py

* Update BinarySearchTree.py

* Update BinarySearchTree.py

* Update BinarySearchTree.py

* Update README.md

* Update BinarySearchTree.py

Author: avkaran-singh

README.md

@@ -54,7 +54,7 @@ Community (college) maintained list of Algorithms and Data Structures implementa
 | Data Structure | C | CPP | Java | Python | Golang | JavaScript | C# |
 |:--------------|:----------------:|:----------------:|:----------------:|:-----------------:|:-----------------:|:-----------------:|:-----------------:|
 | [AVL Tree](http://www.geeksforgeeks.org/avl-tree-set-1-insertion)|[:white_check_mark:](avl_tree/avl_tree.c)| |[:white_check_mark:](avl_tree/AvlTree.java) | | | | |
-| [Binary Search Tree](https://en.wikipedia.org/wiki/Binary_search_tree) | | | [:white_check_mark:](binary_search_tree/BinarySearchTree.java) | | [:white_check_mark:](binary_search_tree/binary_search_tree.go) | | |
+| [Binary Search Tree](https://en.wikipedia.org/wiki/Binary_search_tree) | | | [:white_check_mark:](binary_search_tree/BinarySearchTree.java) | [:white_check_mark:](binary_search_tree/BinarySearchTree.py) | [:white_check_mark:](binary_search_tree/binary_search_tree.go) | | |
 | [Linked List](https://en.wikipedia.org/wiki/Linked_list) | [:white_check_mark:](linked_list/linkedList.c.c) | | [:white_check_mark:](linked_list/LinkedList.java) | [:white_check_mark:](linked_list/linked_list.py) | [:white_check_mark:](linked_list/linked_list.go) | [:white_check_mark:](linked_list/linkedList.js) | [:white_check_mark:](linked_list/LinkedList.cs) |
 | [Queue](https://en.wikipedia.org/wiki/Queue_(abstract_data_type)) | | | | [:white_check_mark:](queue/queue.py) | | | |
 | [Stack](https://en.wikipedia.org/wiki/Stack_(abstract_data_type)) | [:white_check_mark:](stack/stack.c) | | [:white_check_mark:](stack/Stack.java) | [:white_check_mark:](stack/stack.py) | [:white_check_mark:](stack/stack.go) | [:white_check_mark:](stack/stack.js) | [:white_check_mark:](stack/Stack.cs) |

binary_search_tree/BinarySearchTree.py

@@ -0,0 +1,134 @@
+class Node(object):
+    # Node for Binary search Tree and set the Node
+    def __init__(self, data):
+        self.data = data
+        self.left = None
+        self.right = None
+
+# insert data in tree
+
+
+def insert(node, data):
+    if node is None:
+        # create a new node
+        node = Node(data)
+        return node
+    else:
+        # go to the left child
+        if data <= node.data:
+            node.left = insert(node.left, data)
+        # got to the right child
+        else:
+            node.right = insert(node.right, data)
+    return node
+
+# seraching data
+
+
+def search(node, data):
+    # if data not present
+    if node is None:
+        return None
+    # go to the left if data is lesser from root
+    if data < node.data:
+        node = search(node.left, data)
+    # go to the right if data is greater from root
+    elif data > node.data:
+        node = search(node.right, data)
+    # data found
+    elif data == node.data:
+        return node
+    return node
+
+# find the minimum
+
+
+def minright(node):
+    if node.left is None:
+        return node
+    else:
+        node = minright(node.left)
+    return node
+
+# delete a node
+
+
+def delete(root, data):
+    if root is None:
+        return root
+    if data < root.data:
+        root.left = delete(root.left, data)
+    elif data > root.data:
+        root.right = delete(root.right, data)
+    # data node is found
+    else:
+        if root.left is None:
+            return root.right
+        elif root.right is None:
+            return root.left
+        # if left or right child is Not None find the the minimum node in right child
+        temp = minright(root.right)
+        root.data = temp.data
+        # recursive delete the minimum node in right child
+        root.right = delete(root.right, temp.data)
+    return root
+
+# print inorder
+
+
+def inorder(root):
+    if root is not None:
+        inorder(root.left)
+        print(root.data)
+        inorder(root.right)
+
+# print preorder
+
+
+def preorder(root):
+    if root is not None:
+        print(root.data)
+        preorder(root.left)
+        preorder(root.right)
+
+# print postorder
+
+
+def postorder(root):
+    if root is not None:
+        preorder(root.left)
+        preorder(root.right)
+        print(root.data)
+
+# check the method
+
+
+def main():
+    root = None
+    root = insert(root, 5)
+    root = insert(root, 11)
+    root = insert(root, 3)
+    root = insert(root, 1)
+    root = insert(root, 50)
+    root = insert(root, 45)
+    root = insert(root, 30)
+    root = insert(root, 35)
+    print("****** InOrder ******")
+    inorder(root)
+    print("****** PreOrder ******")
+    preorder(root)
+    print("****** PostOrder ******")
+    postorder(root)
+    print("***** search Node ******")
+    temp = search(root, 28)
+    if temp is not None:
+        print("node search==> ", temp.data)
+    else:
+        print("node is not present")
+    print("***** delete Node ******")
+    root = delete(root, 11)
+    inorder(root)
+
+
+if __name__ == '__main__':
+    main()