#include <iostream>
#include <vector>
#include <list>
#include <deque>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <limits>

using namespace std;

#define FOR(x,y) for(int x = 0;x < (y);x++)
#define LLI long long int
#define FORR(x,arr) for(auto& x:arr)
#define ALL(a) (a.begin()),(a.end())

#define _L(x) cout<<(x)<<endl
//#define _L(x) ;

template<int um> class UF {
public:
    vector<int> _parent,_rank;
    UF()
    {
        _parent=_rank=vector<int>(um,0);
        for(int i=0;i<um;i++)
        {
            _parent[i]=i;
        }
    }
    
    int Find(int x)
    {
        if(_parent[x] == x)
        {
            return x;
        }
        _parent[x] = Find(_parent[x]);
        return _parent[x];
    }
    
    int Union(int x,int y)
    {
        int xRoot = Find(x);
        int yRoot = Find(y);
        if(_rank[xRoot]>_rank[yRoot])
        {
            _parent[xRoot] = yRoot;
           return yRoot;
        }
        if(_rank[xRoot]<_rank[yRoot])
        {
            _parent[yRoot] = xRoot;
            return xRoot;
        }
        if(xRoot != yRoot)
        {
            _parent[yRoot] = xRoot;
            _rank[xRoot]++;
            return xRoot;
        }
        return xRoot;
    }
};

string Trim(string source)
{
    string text;
    bool first = true;
    FORR(r, source)
    {
        if(r == '0' && first)
        {
            continue;
        }
        first = false;
        text += r;
    }
    return text;
}

LLI ToLLI(string source, LLI seed)
{
    LLI sum = 0;
    LLI s = 1;
    for(int i = 0;i < source.length();i++)
    {
        char r = source[source.length()-1-i];
        if(r >= 'A' && r <= 'Z')
        {
            LLI c = r - 'A' + 10;
            sum += c * s;
        }
        else
        {
            LLI c = r - '0';
            sum += c * s;
        }
        s *= seed;
    }
    return sum;
}

int main() {

    int n;
    cin >> n;
    
    vector<string> data(n);
    FOR(i, n)
    {
        cin >> data[i];
        data[i] = Trim(data[i]);
    }
    LLI value = numeric_limits< long long >::max();
    FOR(i, n)
    {
        int maxValue = 2;
        FORR(r, data[i])
        {
            if(r >= 'A' && r <= 'Z')
            {
                maxValue = max(maxValue, r - 'A' + 11);
            }
            else
            {
                maxValue = max(maxValue, r - '0' + 1);
            }
        }
        LLI l = ToLLI(data[i], maxValue);
        value = min(value, l);
    }
    cout << value << endl;
    return 0;
}