Question

WAP to perform 4 basic mathematical calculations (addition,subtraction,multiplication and division with remainder and quotient part) with two double data type variables in switch case
print your result other than 1 to 4 print a message for a wrong entry​

Answer 1

Answer:

Calculator using switch-case in Java.

Explanation:

import java.util.Scanner;

public class Calculator {

   public static void main(String[] args) {

       Scanner reader = new Scanner(System.in);

       System.out.print("Enter two numbers: ");

       // nextDouble() reads the next double from the keyboard

       double first = reader.nextDouble();

       double second = reader.nextDouble();

       System.out.print("Enter an operator (+, -, *, /): ");

       char operator = reader.next().charAt(0);

       double result;

       switch(operator)

       {

           case '+':

               result = first + second;

               break;

           case '-':

               result = first - second;

               break;

           case '*':

               result = first * second;

               break;

           case '/':

               result = first / second;

               break;

           // operator doesn't match any case constant (+, -, *, /)

           default:

               System.out.printf("Error! 0perator is not correct (wrong entry)");

               return;

       }

       System.out.printf("%.1f %c %.1f = %.1f", first, operator, second, result);

   }

}

SAMPLE OUTPUT:

Enter two numbers: 1.5

4.5

Enter an operator (+, -, *, /): *

1.5 * 4.5 = 6.8