DSA-lab6(a)-Linear_Search

import java.util.Scanner;

/**
 * LinearSearch Program
 * ---------------------
 * This program searches for an element in an array using Linear Search.
 * 
 * Time Complexity:
 * - Best Case: O(1)
 * - Worst Case: O(n)
 */
public class LinearSearch {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        // Taking input from user
        System.out.print("Enter number of elements: ");
        int n = sc.nextInt();

        int[] arr = new int[n];

        System.out.println("Enter elements:");
        for (int i = 0; i < n; i++) {
            arr[i] = sc.nextInt(); // storing input values
        }

        // Taking element to search
        System.out.print("Enter element to search: ");
        int key = sc.nextInt();

        // Calling linear search function
        int pos = linearSearch(arr, key);

        // Displaying result
        if (pos == -1) {
            System.out.println("Element not found");
        } else {
            System.out.println("Element found at position: " + (pos + 1));
        }

        sc.close(); // closing scanner
    }

    /**
     * Linear Search Algorithm
     * Checks each element one by one until match is found
     */
    public static int linearSearch(int[] arr, int key) {

        // Traverse through array
        for (int i = 0; i < arr.length; i++) {

            // Check if current element matches key
            if (arr[i] == key) {
                return i; // return index if found
            }
        }

        return -1; // return -1 if element not found
    }
}