include <iostream>

using namespace std;

int main() { int sum = 0, number;

while (true) {
    cin >> number; 
    if (number == 0) break; 
    sum += number; 
}

cout << sum; 
return 0;

}

include <iostream>

include <cmath>

using namespace std;

define ll long long

int main() { ll n,m=0; while(cin>>n) { if(n==0) break; else m=m+n;
} cout<<m; }