Binary search on singly linked list

// C program for 
// Binary search on singly linked list
#include <stdio.h>
#include <stdlib.h>

// Linked List LinkNode
struct LinkNode
{
	int data;
	struct LinkNode *next;
};
// Singly linked list 
struct SingleLL
{
	struct LinkNode *head;
	struct LinkNode *tail;
};
// Returns the new linked list
struct SingleLL *newLinkedList()
{
	// Create memory of head and tail Nodes
	struct SingleLL *sll = (struct SingleLL *) malloc(sizeof(struct SingleLL));
	if (sll == NULL)
	{
		printf("Memory overflow\n");
	}
	else
	{
		sll->head = NULL;
		sll->tail = NULL;
	}
	return sll;
}
// Returns the new node of linked list
struct LinkNode *createNode(int data)
{
	// Create dynamic node
	struct LinkNode *node = (struct LinkNode *) malloc(sizeof(struct LinkNode));
	if (node == NULL)
	{
		printf("Memory overflow to Create LinkNode\n");
	}
	else
	{
		// Set initial node value
		node->data = data;
		node->next = NULL;
	}
	return node;
}
// Handles the request of adding new node in linked list
void addNode(struct SingleLL *sll, int data)
{
	struct LinkNode *node = createNode(data);
	if (sll->head == NULL)
	{
		sll->head = node;
	}
	else
	{
		// Append the node at last position
		sll->tail->next = node;
	}
	sll->tail = node;
}
// Display linked list element
void display(struct SingleLL *sll)
{
	if (sll->head == NULL)
	{
		return;
	}
	struct LinkNode *temp = sll->head;
	// iterating linked list elements
	while (temp != NULL)
	{
		printf(" %d →", temp->data);
		// Visit to next node
		temp = temp->next;
	}
	printf(" NULL\n");
}
// Returns the middle node in given range
struct LinkNode *findMiddle(struct LinkNode *first, struct LinkNode *last)
{
	// Define some auxiliary variables
	struct LinkNode *middle = first;
	struct LinkNode *temp = first->next;
	// Find middle node
	while (temp != NULL && temp != last)
	{
		temp = temp->next;
		if (temp != last)
		{
			// Visit to next node
			middle = middle->next;
			temp = temp->next;
		}
	}
	return middle;
}
// This is performing the binary search operation
void binarySearch(struct SingleLL *sll, int value)
{
	if (sll->head == NULL)
	{
		printf("\n Empty Linked List");
		return;
	}
	// Define some auxiliary variables
	struct LinkNode *last = sll->tail;
	struct LinkNode *first = sll->head;
	struct LinkNode *result = NULL;
	struct LinkNode *mid = sll->head;
	if (first->data == value)
	{
		// When search first element
		result = first;
	}
	if (last->data == value)
	{
		// When searching last element
		result = last;
	}
	// This loop is detect given element using binary search
	while (result == NULL && mid != NULL && first != last)
	{
		// First find middle element
		mid = findMiddle(first, last);
		if (mid == NULL)
		{
			// This is useful when we don't know about initially last node 
			// and search element is largest then last node
			result = NULL;
		}
		else if (mid->data == value)
		{
			// When get the find node
			result = mid;
		}
		else if (mid->data > value)
		{
			// Select new last node
			last = mid;
		}
		else
		{
			// Select new starting node
			first = mid->next;
		}
	}
	if (result != NULL)
	{
		printf("\n Given element %d are Present", value);
	}
	else
	{
		printf("\n Given element %d are not Present", value);
	}
}
int main(int argc, char
	const *argv[])
{
	struct SingleLL *sll = newLinkedList();
	//  1 → 7 → 13 → 16 → 25 → 29 → 34 → 39 → NULL
	addNode(sll, 1);
	addNode(sll, 7);
	addNode(sll, 13);
	addNode(sll, 16);
	addNode(sll, 25);
	addNode(sll, 29);
	addNode(sll, 34);
	addNode(sll, 39);
	printf("\n Linked List  : ");
	display(sll);
	// Test Cases
	binarySearch(sll, 34);
	binarySearch(sll, 20);
	binarySearch(sll, 42);
	binarySearch(sll, 39);
	binarySearch(sll, 16);
	return 0;
}

input

 Linked List  :  1 → 7 → 13 → 16 → 25 → 29 → 34 → 39 → NULL

 Given element 34 are Present
 Given element 20 are not Present
 Given element 42 are not Present
 Given element 39 are Present
 Given element 16 are Present