Somehow I got operator looping till I get correct input. When i try to put num1 or num2 in "if" statement, It says that I cannot convert "int" to "boolean". Please help

public class main {

public static void main(String[] args) {
    int num1;
    int num2;
    String operator;
    
    Scanner scan = new Scanner(System.in);  
    System.out.print("tell me first number: ");
        num1 = scan.nextInt();               //<--input only numbers, loop if not   
    System.out.print("tell me second number: ");
        num2 = scan.nextInt();               //<--input only numbers, loop if not
//////////////////operator////////////////////////
    System.out.print("tell me operator: ");
        operator = scan.next();
            while(true) {   
                if(operator.equals(" ")) {
                    System.out.println("answer is: "  (num1   num2));
                    break;
                }
                else if(operator.equals("-")) {
                    System.out.println("answer is: "  (num1 - num2));
                    break;
                }   
                else if(operator.equals("*")) {
                    System.out.println("answer is: "  (num1 * num2));
                    break;
                }
                else if(operator.equals("/")) {
                    System.out.println("answer is: "  (num1 / num2));
                    break;
                }
                else {
                    System.out.print("wrong input! try again!: ");
                    operator = scan.next();
                }   
            }
    }
}

CodePudding user response：

Try this.

    System.out.print("tell me first number: ");
    while (!scan.hasNextInt()) scan.next();
    num1 = scan.nextInt();
    System.out.print("tell me second number: ");
    while (!scan.hasNextInt()) scan.next();
    num2 = scan.nextInt();

CodePudding user response：

    System.out.print("tell me first number: ");
    while (!scan.hasNextInt()) scan.next();
    num1 = scan.nextInt();
    System.out.print("tell me second number: ");
    while (!scan.hasNextInt()) scan.next();
    num2 = scan.nextInt();

With this, wrong answer was looping till i got correct input, but I could not get it to print me "Wrong Input! Try again!: " with wrong input without starting to loop infinitely, so i tried to edit and came up with this.

//////////////////first number//////////////////// 
      System.out.print("tell me first number: ");
          while(!scan.hasNextInt()) { 
              System.out.print("Wrong Input! Try again!: "); scan.next();         
                  if(scan.hasNextInt() == true) {
              }
          }   
              num1 = scan.nextInt();
  //////////////////second number///////////////////  
      System.out.print("tell me second number: ");
          while(!scan.hasNextInt()) {
              System.out.print("Wrong input! Try again!: "); scan.next();
                  if(scan.hasNextInt() == true) {
              }
          }
              num2 = scan.nextInt();

Somehow it helped lol. Thanks @英語は苦手 for help.