import java.util.*;

class Main {
    public static void main(String args[]) {
        Scanner s = new Scanner(System.in);
        String i = s.nextLine();
        Scanner st = new Scanner(i);
        if (st.hasNextLong) {
            System.out.println("true");
        } else {
            System.out.println("false");
        }
        
       
    }
}