import java.util.Scanner;
public class E2_3 {
    public static void main (String args [ ]) {
        System.out.println("请输入若干个数,每输入一个数回车确认");
        System.out.println("最后输入数字0结束输入操作");
        Scanner reader = new Scanner(System.in);
        double sum = 0;
        double x = reader.nextDouble();
        while(x!=0){
           sum = sum+x;
           x = reader.nextDouble();
        }
        System.out.println("sum="+sum);
    }
}