#include <iostream>
#include <limits.h>
using namespace std;

int main() {
    string s;
    int i, j, base, n, N;
    char max;
    long long num, p, sum, min = LLONG_MAX;
    int list[1000];
    cin >> N;
    for (j = 0; j < N; j++) {
        sum = 0;
        p = 1;
        cin >> s;
        n = s.size();
        max = s[0];

        for (i = 0; i < n; i++) {

            if (max < s[i]) max = s[i];
            if (s[i] >= '0' && s[i] <= '9') list[n - 1 - i] = (int)s[i] - 48;
            else list[n - 1 - i] = (int)s[i] - 55;
        }

        if (max < 'A') base = (int)max - 48 + 1;
        else base = (int)max - 55 + 1;

        for (i = 0; i < n; i++) {
            sum += list[i] * p;
            p *= base;
        }

        if (sum < min) min = sum;
    }

    cout << min << endl;

    return 0;
}