Create Prog.java

java/Prog.java

@@ -0,0 +1,59 @@
+// Java implementation of recursive Binary Search
+import java.util.*;
+class BinarySearch {
+	// Returns index of x if it is present in arr[l..
+	// r], else return -1
+	int binarySearch(int arr[], int l, int r, int x)
+	{
+		if (r >= l) {
+			int mid = l + (r - l) / 2;
+
+			// If the element is present at the
+			// middle itself
+			if (arr[mid] == x)
+				return mid;
+
+			// If element is smaller than mid, then
+			// it can only be present in left subarray
+			if (arr[mid] > x)
+				return binarySearch(arr, l, mid - 1, x);
+
+			// Else the element can only be present
+			// in right subarray
+			return binarySearch(arr, mid + 1, r, x);
+		}
+
+		// We reach here when element is not present
+		// in array
+		return -1;
+	}
+
+	// Driver method to test above
+	public static void main(String args[])
+	{
+		Scanner sc=new Scanner(System.in);
+		System.out.print("Enter the number of elements you want to store: ");  
+		//reading the number of elements from the that we want to enter  
+		int n=sc.nextInt();  
+		//creates an array in the memory of length 10  
+		int[] arr = new int[n];  
+		System.out.println("Enter the elements of the array: ");  
+		for(int i=0; i<n; i++)  
+		{  
+		//reading array elements from the user   
+		arr[i]=sc.nextInt();  
+		}  
+		BinarySearch ob = new BinarySearch();
+
+
+		System.out.println("Enter the key to search: ");  
+		int x =sc.nextInt();
+		int result = ob.binarySearch(arr, 0, n - 1, x);
+		if (result == -1)
+			System.out.println("Element not present");
+		else
+			System.out.println("Element found at index "
+							+ result);
+	}
+}
+/* This code is contributed by Rajat Mishra */