Given a sorted array of size N and an integer K, find the position at which K is present in the array using binary search.

Example 1:

Input:
N = 5
arr[] = {1 2 3 4 5} 
K = 4
Output: 3
Explanation: 4 appears at index 3.

Example 2:

Input:
N = 5
arr[] = {11 22 33 44 55} 
K = 445
Output: -1
Explanation: 445 is not present.

Your Task:  
You dont need to read input or print anything. Complete the function binarysearch() which takes arr[], N and K as input parameters and returns the index of K in the array. If K is not present in the array, return -1.

Expected Time Complexity: O(LogN)
Expected Auxiliary Space: O(LogN) if solving recursively and O(1) otherwise.

Constraints:
1 <= N <= 10⁴
1 <= arr[i] <= 10⁴