// No.164 ちっちゃくないよ！！
// https://yukicoder.me/problems/no/164
//

#include <iostream>
#include <cmath>
#include <vector>
#include <string>
using namespace std;

unsigned long long int solve(vector<string> &V);


int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    unsigned int N;
    cin >> N;
    vector<string> V(N);
    for (auto i = 0; i < N; ++i)
        cin >> V[i];

    unsigned long long ans = solve(V);
    cout << ans << endl;
}

unsigned long long int solve(vector<string> &V) {
    unsigned long long ans = pow(2, 63);

    for (string v: V) {
        size_t idx;
        size_t l = v.size();
        for (auto i = 0; i < l; ++i) {
            if (v[i] == '0')
                v[i] = ' ';
            else
                break;
        }
        for (int base = 2; base <= 36; ++base) {
            try {
                unsigned long long t = stoull(v, &idx, base);
                if (idx == l) {
                    ans = min(ans, t);
                    break;
                }
            } catch (invalid_argument& e){
                ;
            }
        }
    }
    return ans;
}