import java.util.Scanner;

class InputTypeError extends Exception {
    private String value;
    InputTypeError(String value) {
        this.value = value;
    }
    @Override
    public String toString() {
        return "Hiba! A megadott érték hibás: " + this.value;
    }
}
public class App {
    public static void main(String[] args) throws InputTypeError {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Szám: ");
        String input = scanner.nextLine();
        scanner.close();
        if(!input.matches("^[0-9]+$")) {
            throw new InputTypeError(input);
        }
        
    }
}