#include <bits/stdc++.h>
using namespace std;

#define all(x) begin(x), end(x)
#ifdef local
#include <experimental/iterator>
#define safe cerr<<__PRETTY_FUNCTION__<<" line "<<__LINE__<<" safe\n"
#define debug(a...) debug_(#a, a)
#define orange(a...) orange_(#a, a)
void debug_(const char *s, auto ...a) {
  cerr << "\e[1;32m(" << s << ") = (";
  int f = 0;
  (..., (cerr << (f++ ? ", " : "") << a));
  cerr << ")\e[0m\n";
}
void orange_(const char *s, auto L, auto R) {
  cerr << "\e[1;33m[ " << s << " ] = [ ";
  using namespace experimental;
  copy(L, R, make_ostream_joiner(cerr, ", "));
  cerr << " ]\e[0m\n";
}
#else
#define safe ((void)0)
#define debug(...) safe
#define orange(...) safe
#endif

int pw(int e, int p) {
  int r = 1;
  while (p--)
    r *= e;
  return r;
}

int64_t cdiv(int64_t x, int64_t y) {
  return (x + y - 1) / y;
}

int main() {
  cin.tie(nullptr) -> sync_with_stdio(false);
  int n;
  cin >> n;
  vector<string> s(n);
  for (int i = 0; i < n; i++) {
    cin >> s[i];
    assert(s[i].size() == s[0].size());
  }

  const int L = s[0].size() - 2;
  const int C = pw(10, L);
  debug(C);

  vector<int> p(n);
  for (int i = 0; i < n; i++)
    p[i] = int(stold(s[i]) * C);

  for (int k = 1; k <= C; k++) {
    int64_t lsum = 0, rsum = 0;
    for (int i = 0; i < n; i++) {
      int64_t l = p[i] == 0 ? 0 : cdiv(k * (p[i] * 2 - 1), C * 2);
      int64_t r = cdiv(k * (p[i] * 2 + 1), C * 2) - 1;

      lsum += l;
      rsum += r;

      // P[i] - (1/2) 10^{-L} <= D[i] / K < P[i] + (1/2) 10^{-L}
      //
      // P[i] * 2C - 1 <= D[i] / K * 2C < P[i] * 2C + 1
      //
      // K * (P[i] * 2C - 1) / (2C)
    }

    if (lsum <= k && k <= rsum) {
      cout << k << '\n';
      return 0;
    }
  }
}