#include <bits/stdc++.h>
using namespace std;
string addone(string s) {
  int c = 1;
  for (int i = s.length() - 1; i >= 0; --i) {
    if (c == 0) {
      return s;
    } else {
      int tmpc = (c + (s[i] - '0')) / 10;
      s[i] = (c + (s[i] - '0')) % 10 + '0';
      c = tmpc;
    }
  }
  if (c) {
    return "1" + s;
  }
  return s;
}
bool greaters(string a, int i, string b) {
  if (a.length() > b.length()) {
    return true;
  } else {
    for (int i = 0; i < a.length(); ++i) {
      if (a[i] > b[i]) return true;
      if (a[i] < b[i]) return false;
    }
    return false;
  }
}
int main() {
  int n;
  string s;
  cin >> n >> s;
  if (n > s.length()) {
    cout << 1;
    for (int i = 1; i < n; ++i) cout << 0;
    cout << endl;
  } else {
    int len = s.length() / n;
    string res = "";
    if (s.length() % n == 0) {
      string tmp = s.substr(0, n);
      string tp = "";
      for (int i = 0; i < len; ++i) tp = tp + tmp;
      if (greaters(tp, 0, s)) {
        res = tp;
      } else {
        for (int i = 0; i < len; ++i) res = res + addone(tmp);
        if (addone(tmp).length() > tmp.length()) {
          res = "";
          string tmp = '1' + string(n - 1, '0');
          int size = s.length() + 1;
          while (size > 0) {
            res += tmp;
            size -= n;
          }
        }
      }
    } else {
      string tmp = '1' + string(n - 1, '0');
      int size = s.length();
      while (size > 0) {
        res += tmp;
        size -= n;
      }
    }
    cout << res << endl;
  }
  return 0;
}
