rb tree added and right rotate case of avl tree corrected

Author: Bibeknam

data-structures/avl-trees/AVLTree.cpp

@@ -284,7 +284,7 @@ class AVLTree {
 		if (y->right != nullptr) {
 			y->right->parent = x;
 		}
-		x->parent = y->parent;
+		y->parent = x->parent;
 		if (x->parent == nullptr) {
 			this->root = y;
 		} else if (x == x->parent->right) {

data-structures/avl-trees/AVLTree.java

@@ -267,7 +267,7 @@ void rightRotate(Node x) {
 		if (y.right != null) {
 			y.right.parent = x;
 		}
-		x.parent = y.parent;
+		y.parent = x.parent;
 		if (x.parent == null) {
 			this.root = y;
 		} else if (x == x.parent.right) {

data-structures/avl-trees/avl_tree.py

@@ -215,7 +215,7 @@ def rightRotate(self, x):
 		if y.right != None:
 			y.right.parent = x
 
-		x.parent = y.parent;
+		y.parent = x.parent;
 		if x.parent == None:
 			self.root = y
 		elif x == x.parent.right: