Create order-agnostic-binary-search.java

algorithms/Java/searching/order-agnostic-binary-search.java

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+/*
+  Order Agnostic Binary Search is a method of finding the sorting in either ascending or descending order.
+*/
+
+public class OrderAgnosticBS {
+    public static void main(String[] args) {
+        int[] arr={1,2,3,4,5,6,7,8,9};
+        int target=7;
+        int ans=orderAgnosticBS(arr,target);
+        System.out.println(ans);
+    }
+    static int orderAgnosticBS(int[] arr,int target){
+        int start=0;
+        int end=arr.length-1;
+        //find array is sorted in ascending or descending order
+        boolean isAsc;// boolean isAsc = arr[start]<arr[send];
+        if(arr[start]<arr[end]){
+            isAsc=true;
+        }
+        else{
+            isAsc=false;
+        }
+        while(start<=end){
+            int mid=start+(end-start)/2;
+            if(arr[mid]==target){
+                return mid;
+            }
+            if(isAsc) {
+                if(arr[mid]>target) {
+                    end=mid-1;
+                }
+                else if(arr[mid]<target){
+                    start=mid+1;
+                }
+            }
+            else{
+                if(arr[mid]<target) {
+                    end=mid-1;
+                }
+                else if(arr[mid]>target){
+                    start=mid+1;
+                }
+            }
+        }
+        return -1;
+    }
+}