#include <iostream>
#include <string>
using namespace std;

int main()
{
	string s,sum;
	int C;
	int count,len0,len1;

	sum = "0";
	while (1)
	{
		cin >> s;
		if (s == "0") break;

		if (sum.length() <= s.length()) {
			string temp;
			temp = sum;sum = s;s = temp;
			sum.insert(0,"0");
		}
		int len = s.length();
		for (int j = 0;j < sum.length() - len;j++)
		s.insert(0,"0");
	//每次输入加数以后，都会在加数前面补一个‘0’，用于最高位进位。		
		C = 0;
		for (int j = s.length() - 1;j >= 0;j--)
		{
			sum[j] += s[j] - '0' + C;
			if (sum[j] >= '0' + 10) {
				sum[j] -= 10;
				C = 1;
			}
			else C = 0;
		}
	}

	if (sum != "0") {
		int index = sum.find_first_not_of("0");
		if (index != string::npos)
			sum = sum.substr(index);
		else sum = "0";
			cout << sum << endl;
	}
	return 0;
}