#include <bits/stdc++.h>
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);
// VAR(int, x);
#define VAR(type, ...)type __VA_ARGS__;Scan(__VA_ARGS__);
template<typename T> void Scan(T& t){std::cin >> t;}
template<typename First,typename...Rest>void Scan(First& first,Rest&...rest){std::cin>>first;Scan(rest...);}
#define OUT(d) std::cout<<(d);
#define FOUT(n, d) std::cout<<std::fixed<<std::setprecision(n)<<(d);
#define SOUT(n, d) std::cout<<std::setw(n)<<(d);
#define SP std::cout<<" ";
#define TAB std::cout<<"\t";
#define BR std::cout<<"\n";
#define ENDL std::cout<<std::endl;
#define FLUSH std::cout<<std::flush;
#define VEC(type, c, n) std::vector<type> c(n);for(auto& i:c)std::cin>>i;
#define MAT(type, c, m, n) std::vector<std::vector<type>> c(m, std::vector<type>(n));for(auto& r:c)for(auto& i:r)std::cin>>i;
#define ALL(a) (a).begin(),(a).end()
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define RFOR(i, a, b) for(int i=(b)-1;i>=(a);--i)
#define REP(i, n) for(int i=0;i<(n);++i)
#define RREP(i, n) for(int i=(n)-1;i>=0;--i)
#define PAIR std::pair<int, int>
#define IN(a0, y, a1, b0, x, b1) (a0<=y && y<a1 && b0<=x && x<b1)
#define SHOW(d) {std::cout << #d << "\t:" << d << "\n";}
#define SHOWVECTOR(v) {std::cout << #v << "\t:";for(auto i : v){std::cout << i << " ";}std::cout << "\n";}
#define SHOWVECTOR2(v) {std::cout << #v << "\t:\n";for(auto i : v){for(auto j : i){std::cout << j << " ";}std::cout << "\n";}}
#define SHOWPAIRVECTOR(v) {for(auto i:v){std::cout<<'('<<i.first<<", "<<i.second<<") ";}std::cout<<"\n";}
//#define int ll
using ll = long long;
const int INF = 1<<30;

int ConvBase(char c){
    if('0'<=c && c<='9'){
        return c-'0';
    }else{
        return c-'A'+10;
    }
}

signed main(){
    INIT;
    VAR(int, n);
    VEC(std::string, s, n);
    ll base = 0;
    std::string min = s[0];
    REP(i, n){
        while(s[i][0]=='0') s[i].erase(s[i].begin());
        if(min.size()>s[i].size()){
            min = s[i];
        }else if(min.size()==s[i].size()){
            min = std::min(min, s[i]);
        }
    }
    int size = min.size();
    REP(i, size){
        base = std::max(int(base), ConvBase(min[i])+1);
    }
    ll ans = 0;
    REP(i, size){
        ll t = ConvBase(min[i]);
        REP(j, size-i-1){
            t *= base;
        }
        ans += t;
    }
    OUT(ans)BR;
    return 0;
}