// This program reads numbers from the user until a particular
// value called a "sentinel" (-1) is entered.
//
// This version of the program uses a "forever" loop with a break statement.

import java.util.*;

public class Sentinel {
    public static void main(String[] args) {
        Scanner console = new Scanner(System.in);
        int sum = 0;
        
        // fencepost solution -- read first number outside loop
        int inputNumber;

        // read more numbers and add into sum, if not -1
        while (true) {
            inputNumber = getNumber(console);
            if (inputNumber == -1) {
                break;
            }
            sum += inputNumber;
        }
        
        System.out.println("The total was " + sum);
    }
    
    // reads one integer from the user and returns it
    public static int getNumber(Scanner console) {
        System.out.print("Enter a number (-1 to quit): ");
        int inputNumber = console.nextInt();  // -1
        return inputNumber;
    }
}