//Aideen's Code for P41 {aideen[at]gmail[dot]com}
#include <iostream>
using namespace std;

const int MAX_N = 100 + 10;

int n;
string ans;

string add(string a, string b) {
  string ret = "";
  int carry = 0;
  for (unsigned i=0; i<a.length() || i<b.length() || carry; i++) {
    if (i<a.length()) carry += a[i] - '0';
    if (i<b.length()) carry += b[i] - '0';
    ret.push_back('0'+(carry%10));
    carry /= 10;
  }
  return ret;
}

int main() {
  string s;

  ans = "0";
  cin >> n;
  for (int i=0; i<n; i++) {
    cin >> s;
    reverse(s.begin(), s.end());
    ans = add(ans, s);
  }
  reverse(ans.begin(), ans.end());
  cout << ans << endl;  
  return 0;
}