var i,j,n,m,suma:long64;
    f,g:text;

function rez2(x:longint):longint;
var y,h,rez:longint;
begin
     y:=x;
     x:=x mod 10;
     if x=0 then rez:=0;
     if x=1 then rez:=1;
     if x=2 then
       begin
            h:=y mod 4;
            if h=1 then rez:=2;
            if h=2 then rez:=4;
            if h=3 then rez:=8;
            if h=0 then rez:=6;
        end;
     if x=3 then
       begin
            h:=y mod 4;
            if h=1 then rez:=3;
            if h=2 then rez:=9;
            if h=3 then rez:=7;
            if h=0 then rez:=1;
        end;
     if x=4 then
       begin
            h:=y mod 2;
            if h=1 then rez:=4;
            if h=0 then rez:=6;
        end;
     if x=5 then rez:=5;
     if x=6 then rez:=6;
     if x=7 then
       begin
            h:=y mod 4;
            if h=1 then rez:=7;
            if h=2 then rez:=9;
            if h=3 then rez:=3;
            if h=4 then rez:=1;
        end;
     if x=8 then
       begin
           h:=y mod 4;
           if h=1 then rez:=8;
           if h=2 then rez:=4;
           if h=3 then rez:=2;
           if h=0 then rez:=6;
        end;
     if x=9 then
       begin
            h:=y mod 2;
            if h=1 then rez:=9;
            if h=0 then rez:=1;
        end;
     rez2:=rez;
end;

begin
     assign(f,'cifra.out');
     rewrite(f);
     close(f);
     assign(f,'cifra.in');
     reset(f);
     readln(f,m);
     j:=0;
     while j<m do
          begin
               readln(f,n);
               inc(j);
               suma:=0;
               for i:=1 to n do
                  suma:=(suma+rez2(i)) mod 10;
               assign(g,'cifra.out');
               append(g);
               writeln(g,suma mod 10);
               close(g);
           end;
    close(f);
end.