Linear Search program in java

Java Program for Linear Search (With Example & Explanation)

Introduction

Linear Search is one of the simplest searching algorithms in Java. It is used to find a specific element in an array by checking each element one by one.

This method is easy to understand and works well for small datasets.

Problem Statement
Write a Java program to perform a Linear Search.

Solution

import java.io.*;

public class LinearSearch {

    public static void main(String args[]) throws IOException {

        InputStreamReader in = new InputStreamReader(System.in);

        BufferedReader br = new BufferedReader(in);

        int i, s, n, h = 0;

        // Taking array size input

        System.out.println("Enter length of Array:");

        n = Integer.parseInt(br.readLine());

        int A[] = new int[n];

        // Taking array elements input

        System.out.println("Enter array elements:");

        for (i = 0; i < n; i++) {

            A[i] = Integer.parseInt(br.readLine());

        }

        // Display array elements

        System.out.println("Array elements are:");

        for (i = 0; i < n; i++) {

            System.out.println(A[i]);

        }

        // Input element to search

        System.out.println("Enter element to be searched:");

        s = Integer.parseInt(br.readLine());

        // Linear search logic

        for (i = 0; i < n; i++) {

            if (s == A[i]) {

                System.out.println("Element found at position: " + (i + 1));

                h = 1;

                break;

            }

        }

        // If element not found

        if (h == 0) {

            System.out.println("Element not found");

        }

    }

}

Explanation

• The program first takes the size of the array as input.
• Then it reads all array elements from the user.
• After that, it asks for the element to be searched.
• Using a loop, it compares each element with the target value.
• If a match is found, it prints the position of the element.
• If no match is found, it displays "Element not found".

Sample Output
Case 1: Element Found

Enter length of Array:

5

Enter array elements:

10

20

30

40

50

Array elements are:

10

20

30

40

50

Enter element to be searched:

30

Element found at position: 3

Case 2: Element Not Found

Enter length of Array:

5

Enter array elements:

10

20

30

40

50

Enter element to be searched:

60

Element not found

Key Points

• Linear Search checks elements sequentially.
• Time Complexity: O(n)
• Best for small datasets or unsorted arrays.
• Easy to implement and understand.

Conclusion

Linear Search is a basic but important concept in programming. It helps beginners understand how searching works before moving to advanced algorithms like Binary Search.