import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        /*
        System.out.println("hello");
        Scanner scan = new Scanner(System.in);
        double number = scan.nextDouble();
        double text = Double.parseDouble(scan.next());
        String numberAsString = "55";
        int numberAsInteger = Integer.parseInt(numberAsString);
        System.out.println(numberAsInteger);
        //String text = scan.next();
        System.out.println("Number: " + number + " text: " + text);
        */
        Scanner scan = new Scanner(System.in);
        System.out.print("Enter operation: ");
        char op = scan.next().charAt(0);
        System.out.print("Enter first number: ");
        int numberOne = scan.nextInt();
        System.out.print("Enter second number: ");
        int numnerTwo = scan.nextInt();

        if(op == '+') {
            System.out.print(numberOne + numnerTwo);
            int sum = numberOne + numnerTwo;
            System.out.print("result: " + sum);
        }else if(op == '-') {
            if(numberOne > numnerTwo) {
                System.out.print(numberOne - numnerTwo);
            }else {
                System.out.print("Error");
            }
        }else if(op == '*') {
            System.out.print(numberOne * numnerTwo);
        }else if(op == '/') {
            if(numberOne == 0 || numnerTwo == 0) {
                System.out.print("Error");
            }else {
                System.out.print(numberOne / numnerTwo);
            }
        }else {
            System.out.print("Invalid operation !");
        }

    }
}