AVL failing to insert (c++) [closed] - c++

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I've been working on implementing a normal binary search tree as well as an AVL tree. I've got it mostly figured out, but there's one problem I can't seem to resolve. When I compile and run the driver, the insert fails. No errors on run or compile; it simply doesn't insert. I've even pasted the code from my BST insert into the insert method with the same results. I'll put the implementation below, along with the BST implementation. Any help would be perfect! Forgive me for the semi-messy code. Haven't cleaned it up well yet.
BST Definition
class BSTree {
BSTNode *root;
public:
//constructors
BSTree();
BSTree(int);
//public members
bool isEmpty(); //check if the bst is empty
void insert(int newValue); //inserts an int into the bst. Returns success
bool find(int findMe); //searches bst for int. True if int is in tree
void preorder(); //calls recursive transversal
void inorder(); //calls recursive traversal
void postorder(); //calls recursive transversal
int height(BSTNode *n); // given node only.
int height(); //returns height of whatever node is passed in.
int totalheight(); //returns tot height. height of empty tree = -1
int avgheight(); //returns avg height of tree
int totaldepth(); //returns tot depth. depth of empty tree = -1
int avgdepth(); //returns avg depth of tree
bool remove(int value); //deletes int. returns true if deleted
private:
int depth(BSTNode *n, int count); //depth of node. recursive.
int counter(BSTNode *n); //called by other functions for counting nodes
int totalheight(BSTNode *n); //called from public totalheight
int totaldepth(BSTNode *n, int depth);
int avgheight(BSTNode *n, int th);
bool findRecursive(struct BSTNode *root, int findMe); //called from public find
struct BSTNode* insertRecursive(struct BSTNode *n, int newValue);
void inorderRecursive(BSTNode *n); //traverses tree in inorder
void preorderRecursive(BSTNode *n); //traverses tree in preorder
void postorderRecursive(BSTNode *n); //traverses tree in preorder
};
//----------------------Constructor---------------------------
BSTree::BSTree(){
root = NULL;
} // BSTree
//root value given
BSTree::BSTree(int value){
root = new BSTNode(value);
} //BSTree(int)
//--------------------------insert-------------------------
void BSTree::insert(int newValue){
root = insertRecursive(root,newValue);
} //insert
struct BSTNode* BSTree::insertRecursive(struct BSTNode *n,int newValue){
//base case
if(n==NULL)
return new BSTNode(newValue);
else if (newValue < n->value) {
n->left = insertRecursive(n->left,newValue);
}
else if (newValue > n->value) {
n->right = insertRecursive(n->right,newValue);
}
else; //duplicate: do nothing
return n;
} //insertRecursive
//--------------------------Call in main-------------------------
BSTree *t = new BSTree();
t->insert(50);
Keep in mind, that works perfectly.
AVL
class AVLTree : public BSTree {
BSTNode *root;
public:
//constructors
AVLTree(); //given nothing
AVLTree(int value); //giving root value
//member methods
void insert(int newValue);
private:
struct BSTNode* insert(BSTNode *n, int newValue);
struct BSTNode* rotateLeft(BSTNode *n);
struct BSTNode* rotateRight(BSTNode *n);
struct BSTNode* doubleLeft(BSTNode *n);
struct BSTNode* doubleRight(BSTNode *n);
};
//--------------------------constructors-----------------------
AVLTree::AVLTree(){
root = NULL;
} // AVLTree
//root value given
AVLTree::AVLTree(int value){
root = new BSTNode(value);
} //AVLTree(int)
I won't show the rotate methods because even without them and the normal BST code in, it still doesn't work.
//------------------------------insert------------------------
void AVLTree::insert(int newValue){
root = insert(root, newValue);
}//insert
struct BSTNode* AVLTree::insert(BSTNode* n, int newValue){
if (n == NULL){ //if we are at end of tree. Insert.
return new BSTNode(newValue);
}//if
else if (newValue < n->value) { //move left if newValue smaller than n->value
n->left = insert(n->left,newValue);
if (height(n->left) - height(n->right) == 2){
if(newValue < n->left->value)
n = rotateLeft(n);
else
n = doubleLeft(n);
}//if == 2
}//else if
else if (newValue > n->value) { //move right if newValue bigger
n->right = insert(n->right,newValue);
if (height(n->right) - height(n->left) == 2){
if(newValue > n->right->value)
n = rotateRight(n);
else
n = doubleRight(n);
}//if == 2
}//else if
else; //duplicate. Do nothing.
n->height = max(height(n->left),height(n->right)) + 1;
return n;
}//insert
//--------------------call in main ---------------------------
AVLTree *a = new AVLTree();
a->insert(50);

Answer 1

You have two root variables.
Your AVLTree has its own root member variable, which is used in the methods of AVLTree.
However, the methods of BSTree use the root variable declared in BSTree.
Remove the unnecessary variable from AVLTree.