#include<iostream>
#include<vector>
#include<string>
#include<algorithm>	
#include<map>
#include<set>
#include<utility>
#include<cmath>
#include<cstring>
#include<queue>
#include<stack>
#include<cstdio>
#include<sstream>
#include<iomanip>
#include<assert.h>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define mt make_tuple
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)
using namespace std;
//kaewasuretyuui
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vp;
typedef vector<vp> vvp;
typedef vector<string> vs;
typedef vector<double> vd;
typedef tuple<int,int,int> tp;
typedef vector<tp> vt;
typedef vector<vd> vvd;
typedef pair<int,pii> pip;
typedef vector<pip>vip;
const double PI=acos(-1);
const double EPS=1e-7;
const int inf=1e9;
const ll INF=1e16;
int dx[4]={0,1,0,-1};
int dy[4]={1,0,-1,0};
int main(){
	ll out=5e18;
	string t="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	int n;
	cin>>n;
	rep(i,n){
		ll a=0;
		string s;
		cin>>s;
		for(int j=t.size()-1;j>=0;j--){
			bool h=false;
			rep(k,s.size())if(s[k]==t[j])h=true;
			if(h){
				ll a=0;
				rep(k,s.size()){
					a*=(j+1);
					if(isdigit(s[k]))a+=s[k]-'0';
					else a+=s[k]-'A'+10;
				}
				out=min(out,a);
				break;
			}
		}
	}
	cout<<out<<endl;
}