# binary search using recursion in java

Submitted by Indrajeet Das, on December 13, 2018 . In this algorithm, given a sorted array of n elements, we search this array for the given key element. #4) Binary Search Java Recursion. int binarySearch(int v): returns the location of the value (v) to be searched in the list by using the binary search method using the recursive technique. In the beginning, we divide the array into two halves by finding the mid element of the array. What is binary search? We will use the recursive method to find element in an array. Termination of this algorithm for an unsuccessful search is quite tricky, with low managing to meander over to the right of high, so that low > high and the while loop terminates. Space Complexity Binary Search uses three different variables — start, end and mid. Java | Binary search using recursion: Here, we are implementing a java program for binary search using recursion. The time complexity of linear search is O(N) which results in binary search being much faster with the O(log2N) complexity. Binary search is a divide and conquer algorithm.. Divide and conquer algorithm is process of dividing the input data-set after each iteration. Hence, in order to search an element in array or collection by using binary search techniques, we must ensure that the array or collection is sorted. At this time, the complexity of binary search will be k = log2N. In my previous tutorial, I have discussed Binary search program in c using iterative approach. This post seeks to clarify the idea of recursion using an algorithm that almost begs to be implemented recursively: the binary search. ; Binary search algorithm works on sorted arrays.. We can not apply the binary search to unsorted array. A binary search algorithm is a famous algorithm for searching. The binary search uses a divide and conquer algorithm in which, the arrays or collection is divided into two halves and the item is compared with the middle element of the collection. In this post, I am going to explain how to implement a binary search program in c using recursion. The binary search algorithm starts at the middle of a sorted array or ArrayList and eliminates half of the array or ArrayList in until the desired value is found or all elements have been eliminated. ; In binary search algorithm, after each iteration the size of array is reduced by half. Binary Search: The non-recursive binary search on the left is a function you've seen before. The binary search algorithm is one of the most famous search algorithms in computer science. The binary search algorithm can be written either iteratively or recursively. void readData(): to fill the elements of the array in ascending order. O(logN), which makes it ideal to search a number on a huge list.For example, in order to search a number in a list of 1 million number will take around 210 comparisons compared to 1 million comparisons required by the linear search algorithm. Binary Search is a searching algorithm that search an element in a sorted array in O(logN) time complexity. Given an integer sorted array (sorted in increasing order) and an element x, find the x in given array using binary search.Return the index of x.Return -1 if x is not present in the given array. It maintains a range between two variables low high.This range is cut roughly in half at each step of the algorithm. It allows you to search a value in logarithmic time i.e. This is the primary benefit of using binary search over linear search. Java binary search program using recursion : Binary search is a search algorithm that finds the position of a target value within a sorted collection of data. Linear search algorithm Lastly, we will see the implementation of recursive binary search in java and its explanation. What is Binary Search Binary Search algorithm searches for an element in an ordered list (or, dictionary) using a process in which at every step of the algorithm the list remaining to be searched gets divided by half. I implemented a binary search algorithm using recursion in Java package com.soloworld.binarysearch; /** * * @author soloworld */ public class BinarySearch { private int[] array; public Binary(int nn): constructor to initialize the size n to nn and the other instance variables. Data must be in sorted order to use the binary search algorithm. Iterative approach be k = log2N nn and the other instance variables ) time.. Recursion: Here, we are implementing a java program for binary search use. In a sorted array of n elements, we will use the method. Search this array for the given key element, on December 13, 2018 algorithm, given a array. 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