public class Solution {
public static void main(String args[]) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int a = Integer.parseInt(br.readLine());
int sum = 0;
while (a != -1) {
sum = sum + a;}
{System.out.println(sum-1);}
}}
package com.javarush.task.task04.task0442;
/*
Суммирование
*/
import java.io.*;
public class Solution {
public static void main(String args[]) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int a = Integer.parseInt(br.readLine());
int sum = 0;
while (a != -1) {
sum = sum + a;}
{System.out.println(sum-1);}
}}