#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>
#include<limits>

using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ll, string> pls;

map<char, int> m;

int main()
{
	int N; cin >> N;

	for (char c = 'A',i = 10; c <= 'Z'; c++,i++) {
		m[c] = i;
	}

	ll ans = (ll)1e20;
	for (int i = 0; i < N; i++) {
		string s; cin >> s;
		int mx = 0;
		for (int j = 0; j < s.size(); j++) {
			if (s[j] >= '0' && s[j] <= '9') {
				if (mx < s[j] - '0')
					mx = s[j] - '0';
			}
			else {
				if (m[s[j]] > mx)
					mx = m[s[j]];
			}
		}
		ll sum = 0;
		for (int j = s.size() - 1, i = 0; j >= 0; j--, i++) {
			if (s[j] >= '0' && s[j] <= '9')
				sum += (ll)pow(mx + 1, i)*(s[j] - '0');
			else
				sum += (ll)pow(mx + 1, i)*(m[s[j]]);
		}
		ans = min(ans,sum);
	}
	cout << ans << endl;
	return 0;
}