WAP to Implement Binary Tree using Linked List

This C Program implements binary tree using linked list. Binary Search tree is a binary tree in which each internal node x stores an element such that the element stored in the left subtree of x are less than or equal to x and elements stored in the right subtree of x are greater than or equal to x. This is called binary-search-tree property
Here is source code of the C Program to implement binary tree using linked list. The C program is successfully compiled and run on a Linux system. The program output is also shown below.

Program

#include <stdio.h>
#include <malloc.h>
struct node {
	struct node * left;
	char data;
	struct node * right;
}
;
struct node *constructTree( int );
void inorder(struct node *);
char array[ ] = {
	'A', 'B', 'C', 'D', 'E', 'F', 'G', '', '', 'H'
}
;
int leftcount[ ] = {
	1,   3,   5,   -1,   9,  -1,  -1,   -1,   -1,  -1
}
;
int rightcount[ ] = {
	2,   4,   6,   -1,  -1,  -1,  -1,   -1,   -1,  -1
}
;
void main() {
	struct node *root;
	root = constructTree( 0 );
	printf("In-order Traversal: \n");
	inorder(root);
}
struct node * constructTree( int index ) {
	struct node *temp = NULL;
	if (index != -1) {
		temp = (struct node *)malloc( sizeof ( struct node ) );
		temp->left = constructTree( leftcount[index] );
		temp->data = array[index];
		temp->right = constructTree( rightcount[index] );
	}
	return temp;
}
void inorder( struct node *root ) {
	if (root != NULL) {
		inorder(root->left);
		printf("%c\t", root->data);
		inorder(root->right);
	}
}

Output

In-order Traversal:
D    B    H    E    A    F    C    G