#include <iostream>
#include <algorithm>
#include <stdlib.h>
#include <string>
using namespace std;






int main() {
int n,u,k;
long long ans=9223372036854775807;
cin>>n;
string s;
int a,b;
for(int i=0;i<n;i++){
cin>>s;
b=s.length();
u=0;
k=0;
for(int j=0;j<s.length();j++){
if('0'<= s[j] && '9' >= s[j]) k=s[j]-'0';
else k=s[j]-'A'+10;
if(k>u) u=k;
}
a=u;



long long t,anss;


	anss=0;
	t=1;
	for(int j=b-1;j>-1;j--){
		if('0'<= s[j] && '9' >= s[j]) anss=anss+t*(s[j]-'0');
		else anss=anss+t*(s[j]-'A'+10);
		t=t*(a+1);
		}
	if(anss<ans) ans=anss;
	//cout<<anss<<endl;
}

cout<<ans<<endl;


}