program cifra;
var f,g:text;
    n:int64;
    t,i,j,y,p,s,cj:longint;
begin
assign(f,'cifra.in');
assign(g,'cifra.out');
reset(f);
rewrite(g);
read(f,t);
for y:=1 to t do
  begin
    read(f,n);
    s:=0;
    for j:=1 to n do
      begin
        cj:=j mod 10;
        if (cj=1)then p:=1 else
        if (cj=2)then p:=4 else
        if (cj=3)then p:=7 else
        if (cj=4)then p:=6 else
        if (cj=5)then p:=5 else
        if (cj=6)then p:=6 else
        if (cj=7)then p:=1 else
        if (cj=8)then p:=8 else
        if (cj=9)then p:=1 else
        if (cj=0)then p:=0;
        s:=s+p;
        s:=s mod 10;
      end;
    writeln(g,s mod 10);
  end;
close(f);
close(g);
end.