import java.util.Scanner;

public class Calculator
{
    private static Scanner keyboard;

    public static void main(String[] args)
    {
        
        System.out.println("Welcome to calculator 1.0");
        System.out.println();

        System.out.print("Enter an expression: ");
        String expression = keyboard.nextLine();

        // The user must enter an expression such as 2+3.
        // You can assume that only 1-digit numbers are typed so
        // that you can use expression.charAt(0) to get the first
        // number and so on.

        int number1; // the first number
        int number2; // the second number
        char operation; // the operation (+,-,*,/)

        number1 = expression.charAt(0);
        operation = expression.charAt(1);
        number2 = expression.charAt(2);

        // Now calculate the answer and print it out.
        //
        // Use an if/else statement to handle each operation
        int answer;
        if (operation == '+')
            answer = number1+number2;
        else if (operation == '-')
            answer = number1-number2;
        else if (operation == '*')
            answer = number1*number2;
        else if (operation == '/')
            answer = number1/number2;
            
            else
        {
            System.out.println("Unsupported operation: " + operation);
            return;
        }
        
        System.out.println("The answer is" +answer);
    }
}

private static Scanner keyboard;

private static Scanner keyboard = new Scanner(System.in);

    String myString = null;
    myString.length();

public class MyClass {

    public static void myMethod() {
        System.out.println("No null pointer exception?");
    }


    public static void main(final String[] arguments) {
        MyClass myclass = null;
        myClass.myMethod();
    }
}