Implementation for AVL Tree in C++

C++/Data-Structures/Algorithms/AVL Tree/AVL Tree Implementation.cpp

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+#include<bits/stdc++.h>
+using namespace std;
+
+class Node
+{
+	public:
+	int key;
+	Node* left;
+	Node* right;
+	int height;
+};
+
+// Utility functions
+int height(Node* curr)
+{
+	if(curr == NULL) return 0;
+	return curr->height;
+}
+
+int getBalance(Node* curr)
+{
+	if(curr == NULL) return 0;
+	return (height(curr->left) - height(curr->right));
+}
+
+Node* newNode(int val)
+{
+	Node* node = new Node();
+	node->key = val;
+	node->left = NULL;
+	node->right = NULL;
+	node->height = 1;
+	return (node);
+}
+
+Node* rightRotate(Node* curr)
+{
+	Node* x = curr->left;
+	Node* y = x->right;
+
+	x->right = curr;
+	curr->left = y;
+
+	curr->height = 1 + max(height(curr->left), height(curr->right));
+	x->height = 1 + max(height(x->left),height(x->right));
+	return x;
+}
+
+Node* leftRotate(Node* curr)
+{
+	Node* x = curr->right;
+	Node* y = x->left;
+
+	x->left = curr;
+	curr->right = y;
+
+	curr->height = 1 + max(height(curr->left), height(curr->right));
+	x->height = 1 + max(height(x->left),height(x->right));
+	return x;	
+}
+
+Node* insert(Node* curr, int val)
+{
+	if(curr==NULL) return newNode(val);
+	if(val < curr->key) curr->left = insert(curr->left, val);
+	else if(val > curr->key) curr->right = insert(curr->right, val);
+	else return curr; // Duplicates Not Allowed
+
+	curr->height = 1 + max(height(curr->left),height(curr->right));
+
+	int bal = getBalance(curr);
+
+	if(bal>1 && val < curr->left->key) return rightRotate(curr);
+	else if(bal>1 && val > curr->left->key) 
+	{
+		curr->left = leftRotate(curr->left);
+		return rightRotate(curr);
+	}
+	else if (bal<-1 && val > curr->right->key) return leftRotate(curr);
+	else if(bal<-1 && val<curr->right->key) 
+	{
+		curr->right = rightRotate(curr->right);
+		return leftRotate(curr);
+	}
+	return curr;
+}
+
+void preorder(Node* root)
+{
+	if(root == NULL) return;
+	cout<<root->key<<" ";
+	preorder(root->left);
+	preorder(root->right);
+	return;
+}
+
+void inorder(Node* root)
+{
+	if(root==NULL) return;
+	inorder(root->left);
+	cout<<root->key<<" ";	
+	inorder(root->right);
+	return;
+}
+
+int main()
+{
+	int n;
+	cin>>n;
+	Node* root = NULL;
+	for(int i=n;i>0;i--)
+	{
+		root = insert(root,i);
+	}
+	preorder(root);	
+	cout<<endl;
+	inorder(root);
+}