public int binarySearchIterative(int[] arr, int k) {
		int f = 0;
		int r = arr.length - 1;
		int m;

		while (f <= r) {

			m = (f + r) / 2;

			if (k == arr[m])
				return m;
			else if (k < arr[m])
				r = m - 1;
			else
				f = m + 1;
		}
		return -1;
	}