ZCW-MacroLabs-OOP-ScientificCalculator/calculator.java

import java.util.*;


public class Calculator {


  public static void main(String[] args) {

    double displayNum = 0;
    boolean calcOn = true;
    double num;

    Scanner sc = new Scanner(System.in);

    while (calcOn) {

      System.out.println(displayNum);
      
      System.out.println("Enter an option:  ");
      System.out.println("0 - ENTER NUMBER");
      System.out.println("1 - ADD ");
      System.out.println("2 - SUBTRACT");
      System.out.println("3 - MULTIPLY");
      System.out.println("4 - DIVIDE");
      System.out.println("5 - SQUARE");
      System.out.println("6 - SQUARE ROOT");
      System.out.println("7 - EXPONENT");
      System.out.println("8 - Invert +/-");
      System.out.println("9 - INVERSE");
      System.out.println("10 - SIN");
      System.out.println("11 - COS");
      System.out.println("12 - TAN");
      System.out.println("13 - INVERSE SIN");
      System.out.println("14 - INVERSE COS");
      System.out.println("15 - INVERSE TAN");
      System.out.println("16 - QUIT");
      
      


      int userInput = sc.nextInt();
      //displayNum = userInput;
      System.out.println(displayNum);
      
      switch(userInput) {
        case 0: System.out.println("enter number");
                num = sc.nextDouble();
                displayNum = num;
                break;
        case 1: System.out.println("enter number to ADD to " + displayNum);
                num = sc.nextDouble();
                displayNum = num + displayNum;
                break;
        case 2: System.out.println("enter number to SUBTRACT from " + displayNum);
                num = sc.nextDouble();
                displayNum = displayNum - num;
                break;
        case 3: System.out.println("enter number to MULTIPLY to" + displayNum);
                num = sc.nextDouble();
                displayNum = num * displayNum;
                break;
         case 4: System.out.println("enter number to DIVIDE from " + displayNum);
                num = sc.nextDouble();
                displayNum = displayNum / num;
                break;
         case 5: System.out.println("square result: " + displayNum * displayNum);
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 6: System.out.println("square root result: " + Math.sqrt(displayNum));
                num = sc.nextDouble();
                break;
         case 7: System.out.println("enter an exponent to the number: " + displayNum);
                num = sc.nextDouble();
                displayNum = Math.pow(displayNum, num);
                break;
         case 8: System.out.println("result: " + displayNum * -1);
                num = sc.nextDouble();
                break;
         case 9: System.out.println("result: " + Math.sqrt(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 10: System.out.println("result: " + Math.sin(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 11: System.out.println("result: " + Math.cos(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 12: System.out.println("result: " + Math.tan(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 13: System.out.println("result: " + Math.asin(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 14: System.out.println("result: " + Math.acos(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 15: System.out.println("result: " + Math.atan(displayNum));
                num = sc.nextDouble();
               // displayNum = displayNum * displayNum;
                break;
         case 16: System.out.println("Quitting!");
                calcOn = false;
                break;
         default: break;
                
        } 

    }








  }








}