TREE

GXTechno Tags: c, data, structure, tree, searching

/*searching of tree*/
#include<stdio.h>
struct rec
{
    long num;
    struct rec *left;
    struct rec *right;
};
struct rec *tree=NULL;
struct rec *tree;
struct rec *delnum(long digit,struct rec *r);
struct rec *insert(struct rec *tree,long num);
struct rec *deletenode(long digit,struct rec *tree);
void search(struct rec *tree,long num);
void preorder(struct rec *tree);
void inorder(struct rec *tree);
void postorder(struct rec *tree);
void main()
{
int choice;
long digit;
int element;
    do
      {
        choice=select();
        switch(choice)
         {
           case 1: puts("Enter integer: To quit enter 0");
               scanf("%ld",&digit);
               while(digit!=0)
                {
                   tree=insert(tree,digit);
                   scanf("%ld",&digit);
                }continue;
           case 2: puts("Enter the number to be search");
               scanf("%ld",&digit);
               search(tree,digit);
               continue;
           case 3: puts("\npreorder traversing TREE");
               preorder(tree);continue;
           case 4: puts("\ninorder traversing TREEE");
               inorder(tree);continue;
           case 5: puts("\npostorder traversing TREE");
               postorder(tree);continue;
           case 6: puts("Enter element which do you wanbt delete from  the BST");
                scanf("%ld",&digit);
               deletenode(digit,tree);continue;
           case 7: puts("END");exit(0);
        }
    }while(choice!=7);
}
int select()
{
int selection;
    do
      {
        puts("Enter 1: Insert a node in the BST");
        puts("Enter 2: Search a node in BST");
        puts("Enter 3: Display(preorder)the BST");
        puts("Enter 4: Display(inorder)the BST");
        puts("Enter 5: Display(postorder) the BST");
        puts("Enter 6: Delete the element");
        puts("Enter 7: END");
        puts("Enter your choice");
        scanf("%d",&selection);
             if((selection<1)||(selection>7))
            {
              puts("wrong choice:Try again");
              getch(); }
       }while((selection<1)||(selection>7));
       return (selection);
}
struct rec *insert(struct rec *tree,long digit)
{
    if(tree==NULL)
      {
        tree=(struct rec *)malloc(sizeof(struct rec));
        tree->left=tree->right=NULL;
        tree->num=digit;
      }
     else
      if(digit<tree->num)
        tree->left=insert(tree->left,digit);
     else
      if(digit>tree->num)
        tree->right=insert(tree->right,digit);
     else if(digit==tree->num)
        {
           puts("Duplicate node:program exited");exit(0);
        }
        return(tree);
}
struct rec *delnum(long digit,struct rec *r)
{
struct rec *q;
if(r->right!=NULL)delnum(digit,r->right);
else
q->num=r->num;
q=r;
r=r->left;
}
struct rec *deletenode(long digit,struct rec *tree)
{
struct rec *r,*q;
if(tree==NULL)
{
puts("Tree is empty.");
exit(0);
}
if(digit<tree->num)
deletenode(digit,tree->left);
else
if(digit>tree->num)deletenode(digit,tree->right);
q=tree;
if((q->right==NULL)&&(q->left==NULL))
q=NULL;
else
if(q->right==NULL)tree=q->left;else
if(q->left==NULL)tree=tree=q->right;else
delnum(digit,q->left);
free(q);
}
void search(struct rec *tree,long digit)
{
    if(tree==NULL)
       puts("The number does not exits\n");
   else
    if(digit==tree->num)
    printf("Number=%ld\n" ,digit);
   else
    if(digit<tree->num)
       search(tree->left,digit);
   else
      search(tree->right,digit);
}
void preorder(struct rec *tree)
{
    if(tree!=NULL)
      {
        printf("%12ld\n",tree->num);
        preorder(tree->left);
        preorder(tree->right);
      }
}
void inorder(struct rec *tree)
{
    if(tree!=NULL)
        {
        inorder(tree->left);
        printf("%12ld\n",tree->num);
        inorder(tree->right);
        }
}
void postorder(struct rec *tree)
{
    if(tree!=NULL)
      {
        postorder(tree->left);
        postorder(tree->right);
        printf("%12ld\n",tree->num);
      }

}

/*output of the program*/
Enter 1: Insert a node in the BST
Enter 2: Search a node in BST
Enter 3: Display(preorder)the BST
Enter 4: Display(inorder)the BST
Enter 5: Display(postorder) the BST
Enter 6: Delete the element
Enter 7: END
Enter your choice
2
Enter the number to be search
6
Number=6
Enter 1: Insert a node in the BST
Enter 2: Search a node in BST
Enter 3: Display(preorder)the BST
Enter 4: Display(inorder)the BST
Enter 5: Display(postorder) the BST
Enter 6: Delete the element
Enter 7: END
Enter your choice
3

preorder traversing TREE
           2
           3
           5
           4
           6
           8
Enter 1: Insert a node in the BST
Enter 2: Search a node in BST
Enter 3: Display(preorder)the BST
Enter 4: Display(inorder)the BST
Enter 5: Display(postorder) the BST
Enter 6: Delete the element
Enter 7: END
Enter your choice
7