import java.util.Scanner;

public class SentinelSum {
    public static void main(String[] args) {
        int number, suma=1;
        Scanner sc = new Scanner(System.in);  
        do {
            System.out.print("Type a number: ");
            number = sc.nextInt();
            suma += number;
        } while (number != -1);     
        System.out.print("Sum is " + suma); 
    }
}