import java.util.*;

public class TrailerValue {
	public static void main(String [] args) throws Exception {
		Scanner scanner = new Scanner(System.in);

		System.out.print("Enter a number (-1 to quit): ");
		int grade = scanner.nextInt();
		while (grade >= 0) {
			System.out.println(grade);
			System.out.print("Enter a number (-1 to quit): ");
			grade = scanner.nextInt();
		}
	}
}