#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  int n;
  cin >> n;
  vector<string> s(n);
  rep(i, n) cin >> s[i];
  ll ans = 8e18;
  for (string t : s) {
    int base = 0;
    for (char c : t) {
      if (isdigit(c))
        base = max(base, c - '0');
      else
        base = max(base, c - 'A' + 10);
    }
    base++;
    Debug(base);
    ll cur = 0;
    for (char c : t) {
      cur *= base;
      if (isdigit(c))
        cur += c - '0';
      else
        cur += c - 'A' + 10;
    }
    Debug(cur);
    ans = min(ans, cur);
  }
  cout << ans << endl;
  return 0;
}