Create binarySearchInRotatedArray.java

1_Arrays/binarySearchInRotatedArray.java

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+import java.util.*;
+
+public class binarySearchRotatedArray {
+    public static int findMin(int arr[], int n){
+        int left = 0, right = n-1, mid = (left+right)/2;
+        while(left <= right){
+            mid = (left+right)/2;
+            if(arr[mid-1] >= arr[mid]){
+                return mid;
+            }
+            else if(arr[mid] >= arr[left] && arr[mid] > arr[right]){
+                left = mid+1;
+            }
+            else{
+                right = mid-1;
+            }
+        }
+        return mid;
+    }
+
+    public static int binarySearch(int arr[], int n, int key){
+        int min = findMin(arr, n);
+        int left = 0, right = n-1;
+
+        if(arr[min] <= key && key <= arr[n-1]){ 
+            left = min;
+        } 
+
+        else{ 
+            right = min;
+        } 
+
+        while(left <= right){
+            int mid = (left + right)/2; 
+            if(arr[mid] ==   key){ 
+                return mid; 
+            } 
+            else if(arr[mid] > key){ 
+                right = mid-1; 
+            } 
+            else{ 
+                left = mid+1; 
+            } 
+        }
+        return -1;
+    }
+
+    public static void main(String[] args){
+        // input
+        Scanner sc = new Scanner(System.in);
+        int n = sc.nextInt();
+        int arr[] = new int[n];
+        for(int i = 0; i < n; i++){
+            arr[i] = sc.nextInt();
+        }
+        System.out.println("enter key: ");
+        int key = sc.nextInt();
+
+        int ans = binarySearch(arr, n, key);
+        System.out.println(ans);
+
+        sc.close();
+    }
+}