calculator.java

import java.util.Scanner;
public class Calculator {
    public static void main(String[] args) {
        
        Scanner in = new Scanner(System.in);

        // Take input from user till user press x or X
        int ans = 0;

        while(true){
            // Take operator as input
            System.out.println("Enter the operator :");
            char op = in.next().trim().charAt(0);

            if(op == '+' || op == '-' || op == '*' || op == '/' || op == '%'){
                
                //input the number
                System.out.println("Enter the numbers :");
                    int num1 = in.nextInt();
                    int num2 = in.nextInt();

                if(op == '+'){
                    ans = num1 + num2;
                }
                if(op == '-'){
                    ans = num1 - num2;
                }
                if(op == '*'){
                    ans = num1 * num2;
                }
                if(op == '/'){
                    if(num2 != 0){
                        ans = num1 / num2;
                    }
                }
                if(op == '%'){
                    ans = num1 % num2;
                }             
            }
            else if(op == 'x' || op == 'X'){
                break;
            }
            else{
                System.out.println("Invalid operation !!");
            }

            System.out.println("Your Answer is :" + ans);
        }

    } 
}