// Program to add numbers until a -1 is input, version 1
// Michael Rothstein
// 01/30/2014

#include <iostream>

using std::cin; using std::cout; using std::endl;

int main() {
  int total = 0;
  int number;
  cin >> number;
  while (number != -1){
    total += number;
    cin >> number;
  }
  cout << "Sum is " << total << endl;
}