Implemented binary search tree

Author: KyattPL

data-structures/BinarySearchTree.py

@@ -0,0 +1,101 @@
+class BinarySearchTree:
+    class Node:
+        def __init__(self, value):
+            self.left = None
+            self.right = None
+            self.value = value
+
+    def search(self, root, key):
+        if root is None or root.value == key:
+            return root
+
+        if root.value < key:
+            return self.search(root.right, key)
+
+        return self.search(root.left, key)
+
+    def insert(self, root, node):
+        if root is None:
+            root = node
+        else:
+            if root.value < node.value:
+                if root.right is None:
+                    root.right = node
+                else:
+                    self.insert(root.right, node)
+            else:
+                if root.left is None:
+                    root.left = node
+                else:
+                    self.insert(root.left, node)
+
+    def in_order(self, root):
+        if root:
+            self.in_order(root.left)
+            print(root.value)
+            self.in_order(root.right)
+
+    def pre_order(self, root):
+        if root:
+            print(root.value)
+            self.pre_order(root.left)
+            self.pre_order(root.right)
+
+    def post_order(self, root):
+        if root:
+            self.post_order(root.left)
+            self.post_order(root.right)
+            print(root.value)
+
+    def min_value_node(self, node):
+        current = node
+        while current.left is not None:
+            current = current.left
+        return current
+
+    def max_value_node(self, node):
+        current = node
+        while current.right is not None:
+            current = current.right
+        return current
+
+    def delete_node(self, root, val):
+        if root is None:
+            return root
+
+        if val < root.value:
+            root.left = self.delete_node(root.left, val)
+
+        elif val > root.value:
+            root.right = self.delete_node(root.right, val)
+
+        else:
+            if root.left is None:
+                temp = root.right
+                root = None
+                return temp
+
+            elif root.right is None:
+                temp = root.left
+                root = None
+                return temp
+
+            temp = self.min_value_node(root.right)
+            root.value = temp.value
+            root.right = self.delete_node(root.right, temp.value)
+
+        return root
+
+
+if __name__ == "__main__":
+    x = BinarySearchTree()
+    root = BinarySearchTree.Node(10)
+    x.insert(root, BinarySearchTree.Node(7))
+    x.insert(root, BinarySearchTree.Node(12))
+    x.insert(root, BinarySearchTree.Node(5))
+    x.insert(root, BinarySearchTree.Node(18))
+    x.insert(root, BinarySearchTree.Node(13))
+    x.in_order(root)
+    print()
+    x.delete_node(root, 12)
+    x.in_order(root)