public class LinearSearch {
    public static void mainMethod(Integer key) {
        Integer[] arr = new Integer[]{5, 10, 15, 20, 25};
        Boolean found = false;
 
        for (Integer i = 0; i < arr.size(); i++) {
            if (arr[i] == key) {
                System.debug('Element found at index: ' + i);
                found = true;
                break;
            }
        }
 
        if (!found) {
            System.debug('Element not found.');
        }
    }
}

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