#include <cstdint>
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
using namespace std;

int N;
vector<string> V;
map<size_t, vector<string>> M;

void input(istream& in)
{
	in >> N;
	V.resize(N);
	for (int i = 0; i < N; i++) {
		in >> V[i];
	}
}

struct less_string
{
	bool operator()(const string& a, const string& b) const
	{
		return a < b;
	}
};

int64_t resolve()
{
	int base = 0x7F;
	for (string& s : V) {
		for (char ch : s) {
			if (ch > base) {
				base = ch;
			}
		}
		size_t nz = s.find_first_not_of('0');
		M[s.length() - nz].push_back(s.substr(nz));
	}
	base = (base < 'A') ? (base - '0') : (base - 'A' + 10);
	base++;
	vector<string>& shortest_strings = M.begin()->second;
	string& smallest_value = *min_element(shortest_strings.begin(), shortest_strings.end(), less_string());
	int64_t value = 0;
	for (char ch : smallest_value) {
		value *= base;
		value += (ch < 'A') ? (ch - '0') : (ch - 'A' + 10);
	}
	return value;
}

int main()
{
	input(cin);
	cout << resolve() << endl;
	return 0;
}