Read AVL Trees

Author: CodeRex7

geekforgeeks/trees/AVL-Tree/a.out

@@ -0,0 +1,125 @@
+/*	AVL tree is a self-balancing Binary Search Tree (BST)
+ *	where the difference between heights of left and right 
+ *	subtrees cannot be more than one for all nodes.
+ *	We can guarantee an upper bound of O(Logn) for all 
+ *	operations. The height of an AVL tree is always O(Logn)
+ *	where n is the number of nodes in the tree.
+*/
+
+#include<bits/stdc++.h>
+using namespace std;
+
+struct Node{
+    int data;
+    int height;
+    Node *right,*left;
+};
+
+int height(Node* N){
+    if (N == NULL)
+        return 0;
+    return N->height;
+}
+
+int getBalance(Node* N){
+	if(N == NULL)
+		return 0;
+	return height(N->left) - height(N->right);
+}
+
+Node* newNode(int data){
+    Node* temp=new Node;
+    temp->data=data;
+    temp->height=1;
+    temp->right=NULL;
+    temp->left=NULL;
+    return temp;
+}
+
+Node* rightRotate(Node* y){
+	Node* x=y->left;
+	Node* temp=x->right;
+
+	x->right=y;
+	y->left=temp;
+
+	x->height = max(height(x->left), height(x->right))+1;
+    y->height = max(height(y->left), height(y->right))+1;
+
+	return x;//new root
+}
+
+Node* leftRotate(Node* x){
+	Node* y=x->right;
+	Node* temp=y->left;
+
+	y->left=x;
+	x->right=temp;
+
+	x->height = max(height(x->left), height(x->right))+1;
+    y->height = max(height(y->left), height(y->right))+1;
+
+	return y;//new root
+
+}
+
+Node* insert(Node* temp,int data){
+    if(temp == NULL)
+        return newNode(data);
+    if(data>temp->data)
+        temp->right=insert(temp->right,data);
+    else if(data<temp->data)
+        temp->left=insert(temp->left,data);
+    else
+    	return temp; //no duplicates
+
+    temp->height = 1 + max(height(temp->left), height(temp->right));
+    int balance = getBalance(temp);
+
+    //Left Left Case---------Right Rotation
+    if(balance > 1 && data < temp->left->data)
+    	return leftRotate(temp);
+    //Right Right Case-------Left Rotation
+    if(balance < -1 && data > temp->right->data)
+    	return rightRotate(temp);
+    //Left Right Case--------Left Right Rotation
+    if(balance > 1 && data > temp->left->data){
+    	temp->left = leftRotate(temp->left);
+    	rightRotate(temp);
+    }
+    //Right Left Case--------Right Left Rotation 
+    if(balance < -1 && data < temp->right->data){
+    	temp->right = rightRotate(temp->right);
+    	leftRotate(temp);
+    }
+    return temp;
+}
+
+void preOrder(Node *root)
+{
+    if(root != NULL)
+    {
+        cout<<root->data<<" ";
+        preOrder(root->left);
+        preOrder(root->right);
+    }
+}
+
+int main()
+{
+  Node *root = NULL;
+ 
+  root = insert(root, 10);
+  root = insert(root, 20);
+  root = insert(root, 30);
+  root = insert(root, 40);
+  root = insert(root, 50);
+  root = insert(root, 25);
+ 
+  printf("Preorder traversal of the constructed AVL"
+         " tree is \n");
+  preOrder(root);
+ 
+  return 0;
+}
+

geekforgeeks/trees/AVL-Tree/insert.cpp

@@ -4,7 +4,7 @@ using namespace std;
 struct Node
 {
     int data;
-    struct Node *right,*left;
+    Node *right,*left;
 };
 
 Node* newNode(int data){

geekforgeeks/trees/BST/a.out

@@ -5,7 +5,7 @@ struct Node
 {
     int data;
     int count;
-    struct Node *right,*left;
+    Node *right,*left;
 };
 
 Node* newNode(int data){

geekforgeeks/trees/BST/delete.cpp

@@ -4,7 +4,7 @@ using namespace std;
 struct Node
 {
     int data;
-    struct Node *right,*left;
+    Node *right,*left;
 };
 
 Node* newNode(int data){

geekforgeeks/trees/BST/duplicates.cpp

@@ -4,7 +4,7 @@ using namespace std;
 struct Node
 {
     int data;
-    struct Node *right,*left;
+    Node *right,*left;
 };
 
 Node* newNode(int data){

geekforgeeks/trees/BST/insert.cpp

@@ -4,7 +4,7 @@ using namespace std;
 struct Node
 {
     int data;
-    struct Node *right,*left;
+    Node *right,*left;
 };
 
 Node* newNode(int data){