// Program to add numbers until a -1 is input, version 2
// Michael Rothstein
// 01/30/2014

#include <iostream>

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

int main() {
    int total = 0;   // Contains the sum of all read in numbers.
    while (1){
        int number;
        cin >> number;
	if( number == -1 ) break;
        total += number;
    }
    cout << "Sum is " << total << endl;
}