Question

Java Program that prompts the user and reads in an integer between 0 to 50, inclusively. If the entered value is outside the range, program’s output will display the following message: “Error: the entered number is out of range”, and continually re-prompts the user to enter the integer again until the user enters a valid integer. • Once a valid integer has been entered, program prompts the user and reads in a second integer between -5 to 20, inclusively. If the entered value is outside the range, program’s output will display the following message: “Error: the entered number is out of range”, and continually re-prompts the user to enter the integer again until the user enters a valid integer. • Once both integers have been entered, program prompts for and read in the arithmetic operation that the user wish to perform: addition (+), subtraction (+), multiplication (*), division (/), or modulus (%). If the entered operation is other than those listed, program’s output will display the following message: “Error: Invalid operation”, and exit the program. • The requested operation will be performed, and program’s output will show details of the operation. • Division by zero can occur with the user input. In that scenario, program’s output simply display “Error: Division by zero” and exit the program. • You also need to find out whether the result of the operation is negative, positive or zero and program’s output will display accordingly. • Comments your code (variable declaration, blocks of code, calculation)

Answer 1

import java.util.Scanner;
public class Operations
{
public static void main(String[] args)
{
   Scanner input=new Scanner(System.in);
   System.out.println("Enter first integer between 0 to 50 inclusively");
   int n1=input.nextInt();
   while(true)
   {
      if(n1>=0 && n1<=50)
      break;
      System.out.println("Error: the entered number is out of range");
      System.out.println("Enter first integer between 0 to 50 inclusively");
      n1=input.nextInt();
   }
   System.out.println("Enter second integer between -5 to 20 inclusively");
   int n2=input.nextInt();
   while(true)
   {
      if(n2>=-5 && n2<=20)
      break;
      System.out.println("Error: the entered number is out of range");
      System.out.println("Enter second integer between -5 to 20 inclusively");
      n2=input.nextInt();
   }
   System.out.println("Enter operation you want to perform: addition (+), subtraction (-), multiplication (*), division (/), or modulus (%)");
   char op=input.next().charAt(0);
   int result=0;
   if(op=='+')
   {
   result=n1+n2;
   System.out.printf(String.format("Addition: %d %c %d = %d\n",n1,op,n2,result));
   }
   else if(op=='-')
   {
   result=n1-n2;
   System.out.printf(String.format("Subtraction: %d %c %d = %d\n",n1,op,n2,result));
   }
   else if(op=='*')
   {
   result=n1*n2;
   System.out.printf(String.format("Multiplication: %d %c %d = %d\n",n1,op,n2,result));
   }
   else if(op=='/')
   {
     if(n2==0)
     {
       System.out.println("Error: Division by zero");
       System.exit(0);
      }
      result=n1/n2;
      System.out.printf(String.format("Division: %d %c %d = %d\n",n1,op,n2,result));
   }
   else if(op=='%')
   {
   result=n1%n2;
   System.out.println("Modulus: "+n1+" "+op+" "+n2+"= "+result);
   }
   else
   {
     System.out.println("Error: Invalid operation");
     System.exit(0);
   }
   if(result==0)
   System.out.print("The result is zero");
   else if(result>0)
   System.out.print("The result is positive");
   else
   System.out.println("The result is negative");
}
}
    

Output