Category : Java | Sub Category : Java Programs | By Prasad Bonam Last updated: 2021-04-19 09:08:11 Viewed : 872
It is a search algorithm that finds the position of a target value within a sorted array. Binary search compares the target value to the middle element of the array. Let’s now see how to implement a binary search algorithm.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | package runnerdev;public class BinarySearch {// Java implementation of recursive Binary Search// Returns index of x if it is present in arr[l..// r], else return -1int 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 itselfif (arr[mid] == x)return mid;// If element is smaller than mid, then// it can only be present in left subarrayif (arr[mid] >x)return binarySearch(arr, l, mid - 1, x);// Else the element can only be present// in right subarrayreturn binarySearch(arr, mid + 1, r, x);}// We reach here when element is not present// in arrayreturn -1;}public static void main(String args[]){BinarySearch ob = new BinarySearch();int arr[] = { 2, 3, 4, 10, 40 };int n = arr.length;int x = 40;int result = ob.binarySearch(arr, 0, n - 1, x);if (result == -1)System.out.println("Element not present");elseSystem.out.println("Element found at index " + result);}} |
On executing the above program, it will locate the element present at the particular index
1 | Element found at index 4 |