Question

Please C code for AVL trees -> insert(recursive),height,balance factor,left rotate,right rotate,max and init functions..

Answer 1

#include <stdio.h>

#include<stdlib.h>

struct BSTreeNode

{

int data;

struct BSTreeNode *left;

struct BSTreeNode *right;

int heightOfNode;

};

void InOrder(struct BSTreeNode *root)

{

if(root != NULL)

{

InOrder(root->left);

printf("%d ",root->data);

InOrder(root->right);

}

}

int Treeheight(struct BSTreeNode *root)

{

if (root == NULL)

return 0;

return root->heightOfNode;

}

int max(int a, int b)

{

if(a >= b)

return a;

return b;

}

struct BSTreeNode* GetNode(int data)

{

struct BSTreeNode* temp = (struct BSTreeNode*)

malloc(sizeof(struct BSTreeNode));

temp->data = data;

temp->left = NULL;

temp->right = NULL;

temp->heightOfNode = 1;

return temp;

}

struct BSTreeNode *RightRight(struct BSTreeNode *y)

{

struct BSTreeNode *x = y->left;

struct BSTreeNode *T2 = x->right;

x->right = y;

y->left = T2;

y->heightOfNode = max(Treeheight(y->left), Treeheight(y->right))+1;

x->heightOfNode = max(Treeheight(x->left), Treeheight(x->right))+1;

return x;

}

struct BSTreeNode *LeftLeft(struct BSTreeNode *x)

{

struct BSTreeNode *y = x->right;

struct BSTreeNode *T2 = y->left;

y->left = x;

x->right = T2;

x->heightOfNode = max(Treeheight(x->left), Treeheight(x->right))+1;

y->heightOfNode = max(Treeheight(y->left), Treeheight(y->right))+1;

return y;

}

int getBalanceFactor(struct BSTreeNode *root)

{

if (root == NULL)

return 0;

return Treeheight(root->left) - Treeheight(root->right);

}

struct BSTreeNode* AVLInsert(struct BSTreeNode* node, int key)

{

if (node == NULL)

return(GetNode(key));

if (key < node->data)

node->left = AVLInsert(node->left, key);

else if (key > node->data)

node->right = AVLInsert(node->right, key);

else

return node;

node->heightOfNode = 1 + max(Treeheight(node->left),

Treeheight(node->right));

int balancefactor = getBalanceFactor(node);

if (balancefactor > 1 && key < node->left->data)

return RightRight(node);

if (balancefactor < -1 && key > node->right->data)

return LeftLeft(node);

if (balancefactor > 1 && key > node->left->data)

{

node->left = LeftLeft(node->left);

return RightRight(node);

}

if (balancefactor < -1 && key < node->right->data)

{

node->right = RightRight(node->right);

return LeftLeft(node);

}

return node;

}

int main()

{

struct BSTreeNode *root = NULL;

root = AVLInsert(root, 190);

root = AVLInsert(root, 200);

root = AVLInsert(root, 130);

root = AVLInsert(root, 840);

root = AVLInsert(root, 500);

root = AVLInsert(root, 225);

InOrder(root);

return 0;

}

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SEE OUTPUT

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