Merge pull request DeepNinja07x#74 from ervaibhavkumar/patch-1

Created class which implements binary search tree.

Author: DeepNinja07x

Data Strucrures/BinarySearchTree.py

@@ -0,0 +1,102 @@
+class Node:
+    def __init__(self, key, left=None, right=None, parent=None):
+        self.key = key
+        self.right = right
+        self.left = left
+
+    def hasLeftChild(self):
+        return self.left
+
+    def hasRightChild(self):
+        return self.right
+
+    def isLeaf(self):
+        return not (self.right or self.left)
+
+    def isRoot(self):
+        return not self.parent
+
+    def __str__(self):
+        return self.key
+
+
+class Tree:
+    def __init__(self):
+        self.root = None
+        self.size = 0
+
+    def _addNode(self, current, value):
+        if value < current.key:
+            if current.left != None:
+                self._addNode(current.left, value)
+            else:
+                current.left = Node(value, parent=current)
+        if value > current.key:
+            if current.right != None:
+                self._addNode(current.right, value)
+            else:
+                current.right = Node(value, parent=current)
+
+    def addNode(self, value):
+        if self.root == None:
+            self.root = Node(value)
+        else:
+            self._addNode(self.root, value)
+        self.size += 1
+
+    def _search(self, current, value):
+        if current == None:
+            print("searched value is not in tree")
+            return None
+        if current.key == value:
+            print("value found")
+            return current
+        elif current.key < value:
+            return self._search(current.right, value)
+        elif current.key > value:
+            return self._search(current.left, value)
+
+    def search(self, value):
+        return self._search(self.root, value)
+
+    def getMin(self, current):
+        if current == None:
+            return None
+        if current.left == None:
+            return current
+        else:
+            return self.getMin(current.left)
+
+    def _deleteNode(self, current, value):
+        if current == None:
+            return None
+        if current.key < value:
+            current.right = self._deleteNode(current.right, value)
+        elif current.key > value:
+            current.left = self._deleteNode(current.left, value)
+        else:
+            if current.left == None:
+                tmp = current.right
+                del current
+                return tmp
+            if current.right == None:
+                tmp = current.left
+                del current
+                return tmp
+            replacedNode = self.getMin(current.right)
+            current.key = replacedNode.key
+            current.right = self._deleteNode(current.right, replacedNode.key)
+        return current
+
+    def deleteNode(self, value):
+        self._deleteNode(self.root, value)
+
+    def _prtTree(self, current):
+        if current == None:
+            return
+        print(current.key)
+        self._prtTree(current.left)
+        self._prtTree(current.right)
+
+    def prtTree(self):
+        self._prtTree(self.root)