Binary Search Tree Program in C

March 20, 2025

Searching in Binary Search Tree in C

 

Here, in this page we will discuss searching in binary search tree in C. A binary search tree is a tree in which the data in left sub-tree is less than the root and the data in right sub-tree is greater than the root.Given a Binary Search tree and a key, check whether the key is present in the tree or not.

searching in binary tree

Algorithm :

  • If tree is empty return.
  • Check whether key is greater or smaller than root.
  • If greater, move to the right subtree. Otherwise move to the left subtree.
  • If Key is found return true.
Searching in binary search tree

Priority Queue in C

Tree Traversals: Inorder Postorder Preorder

Inorder Tree Traversal in Binary Tree

Inorder Tree Traversal without Recursion

Preorder Tree Traversal without Recursion

Code in C for Searching in Binary Search Tree

Run 
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

struct node
{
  int data;
  struct node *left;
  struct node *right;
};

struct node *newNode (int data)
{
  struct node *node = (struct node *) malloc (sizeof (struct node));
  node->data = data;
  node->left = NULL;
  node->right = NULL;

  return (node);
}

bool check_element (struct node * root, int key)
{
  // If root is null, element is not found:Backtrack 
  if (root == NULL)
    {
      return false;
    }
  // Check whether same or not
  if (root->data == key)
    {
      return true;
    }

  if (root->data > key)
    {
      // Traverse the left subtree
      return check_element (root->left, key);
    }
  // Else Traverse the right subtree
  else
    {
      return check_element (root->right, key);
    }
}

int main ()
{
  struct node *root = newNode (80);
  root->left = newNode (60);
  root->right = newNode (90);
  root->left->left = newNode (40);
  root->left->right = newNode (70);
  root->left->left->left = newNode (30);
  root->left->left->right = newNode (50);
  if (check_element (root, 50))
    {
      printf ("Found\n");
    }
  else
    {
      printf ("Not Found\n");
    }
  return 0;
}

Output :

Found