> var a,b,c,d,e,m,n,sum:longint;
>    s1,s2:ansistring;
>    s:array[0..10000]of char;
>    ch:char;
> begin
> readln(n);
> s1:='';
> for a:=1 to n do
>  begin
>  readln(ch);
>  s1:=s1+ch;
>  end;
>  s2:='';
>  sum:=0;
> for a:=length(s1) downto 1 do
>  s2:=s2+s1[a];
> for a:=1 to n do
>  begin
>  if s1<s2 then
>   begin
>    inc(sum);
>    s[sum]:=s1[1];
>    delete(s1,1,1);
>    delete(s2,length(s2),1);
>   end
>   else
>   begin
>   inc(sum);
>   s[sum]:=s2[1];
>   delete(s2,1,1);
>   delete(s1,length(s1),1);
>   end;
>  end;
> for a:=1 to sum-1 do
>  write(s[a]);
>  writeln(s[sum]);
> end.