Adding the avl ds tree program in ac

AVL_Tree.c

@@ -0,0 +1,192 @@
+/*Write a program to implement AVL tree with suitable
+operations in C.*/
+#include<stdio.h>
+#include<stdlib.h>
+#include<math.h>
+#include<string.h>
+struct node
+{
+    int data;
+    struct node *left;
+    struct node *right;
+    int height;
+};
+struct node *newnode(int data)
+{
+    struct node *temp=(struct node *)malloc(sizeof(struct node));
+    temp->data=data;
+    temp->left=NULL;
+    temp->right=NULL;
+    temp->height=1;
+    return temp;
+}
+int height(struct node *temp)
+{
+    if(temp==NULL)
+        return 0;
+    return temp->height;
+}
+int max(int a,int b)
+{
+    return (a>b)?a:b;
+}
+struct node *rightrotate(struct node *y)
+{
+    struct node *x=y->left;
+    struct node *T2=x->right;
+    x->right=y;
+    y->left=T2;
+    y->height=max(height(y->left),height(y->right))+1;
+    x->height=max(height(x->left),height(x->right))+1;
+    return x;
+}
+struct node *leftrotate(struct node *x)
+{
+    struct node *y=x->right;
+    struct node *T2=y->left;
+    y->left=x;
+    x->right=T2;
+    x->height=max(height(x->left),height(x->right))+1;
+    y->height=max(height(y->left),height(y->right))+1;
+    return y;
+}
+struct node *insert(struct node *root,int data)
+{
+    if(root==NULL)
+        return newnode(data);
+    if(data<root->data)
+    {
+        root->left=insert(root->left,data);
+        if(height(root->left)-height(root->right)==2)
+        {
+            if(data<root->left->data)
+                root=rightrotate(root);
+            else
+                root=leftrotate(root);
+        }
+    }
+    else if(data>root->data)
+    {
+        root->right=insert(root->right,data);
+        if(height(root->right)-height(root->left)==2)
+        {
+            if(data>root->right->data)
+                root=leftrotate(root);
+            else
+                root=rightrotate(root);
+        }
+    }
+    root->height=max(height(root->left),height(root->right))+1;
+    return root;
+}
+struct node *minvalue(struct node *root)
+{
+    struct node *current=root;
+    while(current->left!=NULL)
+        current=current->left;
+    return current;
+}
+struct node *delete(struct node *root,int data)
+{
+    if(root==NULL)
+        return root;
+    if(data<root->data)
+        root->left=delete(root->left,data);
+    else if(data>root->data)
+        root->right=delete(root->right,data);
+    else
+    {
+        if(root->left==NULL)
+        {
+            struct node *temp=root->right;
+            free(root);
+            return temp;
+        }
+        else if(root->right==NULL)
+        {
+            struct node *temp=root->left;
+            free(root);
+            return temp;
+        }
+        struct node *temp=minvalue(root->right);
+        root->data=temp->data;
+        root->right=delete(root->right,temp->data);
+    }
+    if(root==NULL)
+        return root;
+    root->height=max(height(root->left),height(root->right))+1;
+    if(height(root->left)-height(root->right)==2)
+    {
+        if(height(root->left->left)>height(root->left->right))
+            root=rightrotate(root);
+        else
+            root=leftrotate(root);
+    }
+    else if(height(root->right)-height(root->left)==2)
+    {
+        if(height(root->right->right)>height(root->right->left))
+            root=leftrotate(root);
+        else
+            root=rightrotate(root);
+    }
+    return root;
+}
+void inorder(struct node *root)
+{
+    if(root!=NULL)
+    {
+        inorder(root->left);
+        printf("%d ",root->data);
+        inorder(root->right);
+    }
+}
+void display(struct node *root)
+{
+
+    if(root!=NULL)
+    {
+        printf("%d ",root->data);
+        display(root->left);
+        display(root->right);
+    }
+}
+int main()
+{
+    struct node *root=NULL;
+    int choice,data;
+    while(1)
+    {
+        printf("\n1.Insert 2.Delete 3.Inorder 4.Display 5.Exit: ");
+        scanf("%d",&choice);
+        switch(choice)
+        {
+            case 1:
+                printf("Enter the data: ");
+                scanf("%d",&data);
+                root=insert(root,data);
+                break;
+            case 2:
+                printf("Enter the data: ");
+                scanf("%d",&data);
+                root=delete(root,data);
+                break;
+            case 3:
+                inorder(root);
+                break;
+            case 4:
+                display(root);
+                break;
+
+
+            case 5:
+                exit(0);
+                break;
+            default:
+                printf("Invalid choice\n");
+
+        }
+    }
+
+
+    return 0;
+}