# binary search using recursion in java

In this post, I am going to explain how to implement a binary search program in c using recursion. Data must be in sorted order to use the binary search algorithm. void readData(): to fill the elements of the array in ascending order. 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. The time complexity of linear search is O(N) which results in binary search being much faster with the O(log2N) complexity. It allows you to search a value in logarithmic time i.e. The binary search algorithm can be written either iteratively or recursively. Binary Search is a searching algorithm that search an element in a sorted array in O(logN) time complexity. This is the primary benefit of using binary search over linear search. Binary search is a divide and conquer algorithm.. Divide and conquer algorithm is process of dividing the input data-set after each iteration. It maintains a range between two variables low high.This range is cut roughly in half at each step of the algorithm. This post seeks to clarify the idea of recursion using an algorithm that almost begs to be implemented recursively: the binary search. 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. Submitted by Indrajeet Das, on December 13, 2018 . 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. What is binary search? 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. The binary search algorithm is one of the most famous search algorithms in computer science. In my previous tutorial, I have discussed Binary search program in c using iterative approach. Lastly, we will see the implementation of recursive binary search in java and its explanation. 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. At this time, the complexity of binary search will be k = log2N. Space Complexity Binary Search uses three different variables — start, end and mid. In this algorithm, given a sorted array of n elements, we search this array for the given key element. 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 the beginning, we divide the array into two halves by finding the mid element of the array. ; Binary search algorithm works on sorted arrays.. We can not apply the binary search to unsorted array. Binary(int nn): constructor to initialize the size n to nn and the other instance variables. Linear search algorithm Binary Search: The non-recursive binary search on the left is a function you've seen before. I implemented a binary search algorithm using recursion in Java package com.soloworld.binarysearch; /** * * @author soloworld */ public class BinarySearch { private int[] array; public 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. Java | Binary search using recursion: Here, we are implementing a java program for binary search using recursion. A binary search algorithm is a famous algorithm for searching. 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