Getting segmentation faults at rotations because the code doesn't take into account relationships to the parent nodes. Especially hard to deal with when dealing with the root

program3/AVLCommands.cpp

@@ -73,6 +73,8 @@ int AVLCommands::max(int a, int b) {
 }
 
 int AVLCommands::height(std::shared_ptr<BSTNode> currentNode) {
+	//std::cout << "Updating the height..." << std::endl;
+	//std::cout << "height: " << currentNode->height_ << std::endl;
 	if (root_ == nullptr) {
 		return 0;
 	}
@@ -105,27 +107,28 @@ void AVLCommands::balance(std::shared_ptr<BSTNode> currentNode) {
 	}
 	std::shared_ptr<BSTNode> parent = currentNode->parent_.lock();
 	if (parent != nullptr) {
-		std::cout << "parent node key: " << parent->key_ << std::endl;
-		std::cout << "Rotation to be preformed:" << std::endl;
+		//std::cout << "parent node key: " << parent->key_ << std::endl;
+		std::cout << "balanceFactor at balance: " << parent->balance_ <<std::endl;
+		//std::cout << "Rotation to be preformed:" << std::endl;
 
 		if (parent->balance_ > 1) {
-			if (parent->key_ < currentNode->left_->key_) {
+			if (parent->key_ < parent->left_->key_) {
 				std::cout << "Left-Left" << std::endl;
 				rightRotate(parent);
 				return;
-			} else if (parent->key_ > currentNode->left_->key_) {
+			} else if (parent->key_ > parent->left_->key_) {
 				std::cout << "Left-Right" << std::endl;
 		    parent->left_ =  leftRotate(parent->left_);
 		    rightRotate(parent);
 				return;
 			}
 		} else if (parent->balance_ < -1) {
-			if (parent->key_ < currentNode->right_->key_) {
+			if (parent->key_ < parent->right_->key_) {
 				std::cout << "Right-Right" << std::endl;
-				std::cout << "Parent key input: " << parent->key_ << std::endl;
-				rightRotate(parent);
+				std::cout << "Current Node key input: " << parent->key_ << std::endl;
+				leftRotate(parent);
 				return;
-			} else if (parent->key_ > currentNode->right_->key_) {
+			} else if (parent->key_ > parent->right_->key_) {
 				std::cout << "Right-Left" << std::endl;
 		    parent->right_ = rightRotate(parent->right_);
 		    leftRotate(parent);
@@ -138,14 +141,15 @@ void AVLCommands::balance(std::shared_ptr<BSTNode> currentNode) {
 }
 
 std::shared_ptr<BSTNode> AVLCommands::rightRotate(std::shared_ptr<BSTNode> currentNode){
+	printTree();
 	if (currentNode == nullptr) {
 		std::cout << "Can't rotate on an empty node!" << std::endl;
 		return currentNode;
 	}
 	std::cout << "First, Right Rotate!" << std::endl;
-	std::cout << "Top: " << currentNode;
-	std::cout << ", Middle: " << currentNode->left_;
-	std::cout << ", Last: " << currentNode->left_->right_ << std::endl;
+	std::cout << "Top: " << currentNode->key_;
+	std::cout << ", Middle: " << currentNode->left_->key_;
+	std::cout << ", Last: " << currentNode->left_->right_->key_ << std::endl;
 	std::shared_ptr<BSTNode> x = currentNode->left_;
 	std::cout << "Does the current node have a left node?" << std::endl;
 	std::shared_ptr<BSTNode> T2 = x->right_;
@@ -160,23 +164,37 @@ std::shared_ptr<BSTNode> AVLCommands::rightRotate(std::shared_ptr<BSTNode> curre
 
 	// Return new root
 	return x;
-
-	return currentNode;
 }
 
+// Takes the root of the tree to be left rotated and rotates it to provide new root
 std::shared_ptr<BSTNode> AVLCommands::leftRotate(std::shared_ptr<BSTNode> currentNode){
+	if (currentNode == nullptr) {
+		std::cout << "Can't rotate on an empty node!" << std::endl;
+		return currentNode;
+	}
 	std::cout << "Left Rotate!" << std::endl;
+
 	std::shared_ptr<BSTNode> y = currentNode->right_;
-  std::shared_ptr<BSTNode> T2 = y->left_;
+	y->left_ = currentNode;
 
-  // Perform rotation
-  y->left_ = currentNode;
-  currentNode->right_ = T2;
+	std::shared_ptr<BSTNode> T2 = y->left_;
+	currentNode->right_ = T2;
 
-  //  Update heights
-  currentNode->height_ = max(height(currentNode->left_), height(currentNode->right_))+1;
-  y->height_ = max(height(y->left_), height(y->right_))+1;
 
+	std::cout << "New subtree root: " << y->key_ << std::endl;
+	std::cout << "New left: " << y->left_->key_ << std::endl;
+	std::cout << "New right: " << y->right_->key_ << std::endl;
+	std::cout << "Old subtree root: " << currentNode->key_ << std::endl;
+	//std::cout << "Old left: " << currentNode->left_->key_ << std::endl;
+	std::cout << "Old right: " << currentNode->right_->key_ << std::endl;
+
+	std::cout << "New root: " << root_->key_ << std::endl;
+
+  //  Update heights
+  //currentNode->height_ = max(height(currentNode->left_), height(currentNode->right_))+1;
+  //y->height_ = max(height(y->left_), height(y->right_))+1;
+	//height(y);
+	printTree();
   // Return new root
   return y;
 }
@@ -193,6 +211,9 @@ void AVLCommands::printTree(std::shared_ptr<BSTNode> currentNode){
 		std::cout << "key: " << currentNode->key_ << std::endl;
 		std::cout << "height: " << currentNode->height_ << std::endl;
 		std::cout << "balance: " << currentNode->balance_ << std::endl;
+		if (currentNode->parent_.lock() != nullptr) {
+			std::cout << "parent: " << currentNode->parent_.lock()->key_ << std::endl;
+		}
 		if (currentNode->left_ != nullptr) {
 			std::cout << "left" << std::endl;
 			printTree(currentNode->left_);

program3/BST.cpp

@@ -253,5 +253,6 @@ std::string BST::JSON() const {
 		}
 	}
 	result["size"] = size_;
+	std::cout << result << std::endl;
 	return result.dump(2) + "\n";
 }

program3/Makefile

@@ -5,7 +5,7 @@ OPT=-O3 -std=c++14
 JSON=json.hpp
 
 .PHONY: all
-all: AVLSanityCheck Test
+all: AVLSanityCheck Test bstTest
 #all: BSTSanityCheck CreateData AVLSanityCheck Test
 
 #CreateData: CreateData.cxx json.hpp
@@ -20,6 +20,9 @@ AVLSanityCheck: AVLSanityCheck.cxx AVLCommands.o
 Test: test.cpp AVLCommands.o
 	$(CC) $(DEV) test.cpp AVLCommands.o -o Test.exe
 
+bstTest: bstTest.cpp BST.o
+	$(CC) $(DEV) bstTest.cpp BST.o -o bstTest.exe
+
 BST.o: BST.cpp BST.h
 	$(CC) $(DEV) -c BST.cpp
 

program3/bstTest.cpp

@@ -0,0 +1,29 @@
+// Driver program to test above functions
+#include "BST.h"
+
+int main()
+{
+    BST avl;
+    avl.Insert(2);
+    //avl.printTree();
+    avl.Insert(3);
+    //avl.printTree();
+    avl.Insert(4);
+    //avl.printTree();
+    avl.Insert(5);
+    //avl.printTree();
+    avl.Insert(1);
+    //avl.printTree();
+    avl.Insert(6);
+    //avl.printTree();
+    avl.Insert(7);
+    //avl.printTree();
+    avl.Insert(8);
+    //avl.printTree();
+    avl.Insert(9);
+    //avl.Insert(50);
+    //avl.printTree();
+    avl.Delete(6);
+    avl.JSON();
+    return 0;
+}