program ucif;
var i,us,p,e,n,j:longint; f,g:text; t:integer;
begin
assign (f,'cifra.in');reset(f);
assign (g,'cifra.out');rewrite(g);
readln(f,T);
for i:=1 to T do begin
readln(f,n);
us:=0;
 p:=1;
 for e:=1 to n do begin
 j:=0;
 while j<>e do begin
 inc(j);
    p:= p*n mod 10;
    end;
 us:=(us+p) mod 10;end;
writeln(g,us);
 end;
close(f);
close(g);
end.