#include<vector>
#include<map>
#include<set>
#include<queue>
#include<algorithm>
#include<functional>
#include<numeric>
#include<utility>
#include<sstream>
#include<iostream>
#include<iomanip>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cctype>
#include<string>
#include<bitset>
#include<cstring>
#include<list>
using namespace std;
typedef vector<int>VI;
typedef vector<VI>VVI;
typedef vector<string>VS;
typedef pair<int,int>PII;
typedef long long LL;
typedef pair<LL,LL>PLL;
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define PB push_back
#define EACH(i,c) for(typeof((c).begin())i=(c).begin();i!=(c).end();i++)
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define F first
#define S second

bool comp(const string &s,const string &t){
    if(s.length()!=t.length())return s.length()<t.length();
    REP(i,s.length()){
        int v1=(isdigit(s[i])?s[i]-'0':s[i]-'A'+10);
        int v2=(isdigit(t[i])?t[i]-'0':t[i]-'A'+10);
        if(v1!=v2)return v1<v2;
    }
    return false;
}
int main(){
    VS V;
    int n;
    cin>>n;
    while(n--){
        string str;
        cin>>str;
        while(str[0]=='0'&&str.length()>1){
            str=str.substr(1,str.length()-1);
        }
        V.PB(str);
    }
    sort(V.begin(),V.end(),comp);
    string str=V[0];
    LL d=0;
    LL ma=0;
    REP(i,str.length()){
        LL v=(isdigit(str[i])?str[i]-'0':str[i]-'A'+10);
        ma=max(ma,v);
    }
    ma++;
    REP(i,str.length()){
        d*=ma;
        d+=(isdigit(str[i])?str[i]-'0':str[i]-'A'+10);
    }
    cout<<d<<endl;

    return 0;
}