# Java linear search program

## Linear search

Linear search is a way of finding a target value within a collection of data. It is also known as sequential search. It sequentially checks each element of the collection data for the target value until a match is found or until all the elements have been searched.

## Basic algorithm

Given a collection of data L of n elements with values or records L0 … Ln−1, and target value T, the following subroutine uses linear search to find the index of the target T in L.

• Set i to 0.
• If Li = T, the search terminates successfully; return i.
• Increase i by 1.
• If i < n, go to step 2. Otherwise, the search terminates unsuccessfully.

Note: Linear search is not used commonly because it is slower than binary search and hashing.

## Example

package com.w3spoint;   public class Test { public static int linearSearch(int[] data, int key){ for(int i=0;i<data.length;i++){ if(data[i] == key){ return i; } } return -1; }   public static void main(String args[]){ int[] data= {50,27,30,50,70,9,19}; int key = 9; System.out.println(key+" is found at index: "+linearSearch(data, key)); } }

## Output

9 is found at index: 5