Iterative binary search in C

#include <stdio.h>   

// A iterative binary search function.

// It returns location of x in

// given array arr[l..r] if present, otherwise -1




int binarySearch(int arr[], int l, int r, int x)

{

  while (l <= r)

  {

    int m = l + (r-l)/2;

  

    // Check if x is present at mid

    if (arr[m] == x) 

        return m;  

  

    // If x greater, ignore left half  

    if (arr[m] < x) 

        l = m + 1; 

  

    // If x is smaller, ignore right half 

    else 

         r = m - 1; 

  }

  

  // if we reach here, then element was not present

  return -1; 

}

  

int main(void)

{

   int arr[] = {2, 3, 4, 10, 40};

   int n = sizeof(arr)/ sizeof(arr[0]);

   int x = 10;

   int result = binarySearch(arr, 0, n-1, x);

   (result == -1)? printf("Element is not present in array")

                 : printf("Element is present at index %d", result);

   return 0;