import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		System.out.println("hello");
		Scanner scan = new Scanner(System.in);
		System.out.print("Enter operation");
	    char symbol = scan.next().charAt(0);
		System.out.print("Enter first number: ");
		int number1 = Integer.parseInt(scan.next());
		System.out.print("Enter second number: ");
		int number2 = scan.nextInt();

		if(symbol == '+') {
			System.out.print(number1 + number2);
		}else if(symbol == '-') {
			if(number1 > number2) {
				System.out.print(number1 - number2);
			}else {
				System.out.print("First number mast be greater than second number");
			}
		}else if(symbol == '*') {
			System.out.print(number1 * number2);
		}else if(symbol == '/') {
			if(number2 != 0) {
				System.out.print(number1 / number2);
			}else {
				System.out.print("Second number can't be zero");
			}
		}else {
			System.out.print("Invalid operation");
		}
	}
}