package ARRAYS; //When we dont know wether the sorting is in ascending or descending order.... public class AgnosticBinarySearch { public static void main(String[] args) { int[] arr = {-35, -23, -8, 0, 3, 27, 34, 45, 65, 78, 99}; int target = 45; int[] arr2 = {345, 321, 254, 76, 65, 43, 27, 10, 5, 0, -23, -29}; int target2 = -29; int ans = agnosticBS(arr, target); int ans2 = agnosticBS(arr2, target2); System.out.println(ans); System.out.println(ans2); } static int agnosticBS(int[] arr, int target) { boolean asc = isAsc(arr); int start = 0; int end = arr.length - 1; // int mid= (start+end)/2; --> not a better way as start + end can exceed the range of int while (start <= end) { int mid = start + (end - start) / 2; if (target == arr[mid]) { return mid; } if (asc) { if (target > arr[mid]) { start = mid + 1; } else if (target < arr[mid]) { end = mid - 1; } } else { if (target < arr[mid]) { start = mid + 1; } else if (target > arr[mid]) { end = mid - 1; } } } return -1; } static boolean isAsc(int[] arr) { return arr[0] < arr[arr.length - 1]; } }