#include <iostream>
using namespace std;

const int maxn=105;
int a[maxn];

int main(){
	while(true){
		int n; cin>>n;
		if(n==0) break;
		int sum=0;
		for(int i=1;i<=n;++i){
			cin>>a[i];
			sum+=a[i];
		}
		cout<<sum<<endl;
	}
}