This is my first calculator in Java. I just started learning a week ago so any feedback (positive and negative) is welcome. Tell me what's good and what I can improve on.import java.util.Scanner;public class Calculator {    public static void main(String[] args) {        // Creates scanner object        Scanner scanner = new Scanner(System.in);        // Controls the start and stop of the program        boolean run = true;        // Sets and resets the operand and answer variables        int fnum = 0;        int snum = 0;        int answer = 0;        // While loop that keeps the program running until user exits        while (run) {            // Calculator interface            System.out.println(=====================================);            System.out.println(           Calculator V1.0         );            System.out.println(=====================================);            System.out.println(1. Addition);            System.out.println(2. Subtraction);            System.out.println(3. Multiplication);            System.out.println(4. Division);            System.out.println(5. Exit);            System.out.printf(Please pick an operation(1-5): );            // Prompts user to choose an operation            int operation = scanner.nextInt();            // Does stuff depending on what integer the user enters            switch (operation) {            case 1:                System.out.printf(Enter first number: );                fnum = scanner.nextInt();                System.out.printf(Enter second number: );                snum = scanner.nextInt();                answer = fnum + snum;                System.out.println(The answer is:  + answer);                break;            case 2:                System.out.printf(Enter first number: );                fnum = scanner.nextInt();                System.out.printf(Enter second number: );                snum = scanner.nextInt();                answer = fnum - snum;                System.out.println(The answer is:  + answer);                break;            case 3:                System.out.printf(Enter first number: );                fnum= scanner.nextInt();                System.out.printf(Enter second number: );                snum = scanner.nextInt();                answer = fnum * snum;                System.out.println(The answer is:  + answer);                break;            case 4:                System.out.printf(Enter first number: );                fnum = scanner.nextInt();                System.out.printf(Enter second number: );                snum = scanner.nextInt();                answer = fnum / snum;                System.out.println(The answer is:  + answer);                break;            case 5:                System.out.println(Thank you for using the calculator!);                scanner.close();                run = false;                break;            default:                System.out.println(Invalid operation!);                break;            }        }    }}
Simple beginner Java calculator
java;beginner;calculator