var a: array[1..1000] of byte;
    u: array[1..1000] of boolean;
    t,i, j, k, c, n: integer;
      s: string;
begin
 assign(input,'cifra.in');
 reset(input);
 assign(output,'cifra.out');
 rewrite(output);

 for i:=1 to 1000 do u[i]:=false;
 i:=5;
  while i<=1000
   do Begin
         a[i]:=5; u[i]:=true;
         i:=i+10;
      end;

 i:=6;
  while i<=1000
   do Begin
         a[i]:=6; u[i]:=true;
         i:=i+10;
      end;
 i:=10;
  while i<=1000
   do Begin
         a[i]:=0; u[i]:=true;
         i:=i+10;
      end;


 i:=1;
  while i<=1000
   do Begin
         a[i]:=1; u[i]:=true;
         i:=i+10;
      end;


 i:=-8;
 while i<1000 do begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 4) of
    0 : a[i]:=6;
    1 : a[i]:=2;
    2 : a[i]:=4;
    3 : a[i]:=8;
   end;
   i:=i*2;
  end; i:=c; end;



 i:=-7;
 while i<1000 do begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 4) of
    0 : a[i]:=1;
    1 : a[i]:=3;
    2 : a[i]:=9;
    3 : a[i]:=7;
   end;
   i:=i*3;
  end; i:=c; end;


 i:=-3;
 while i<1000 do Begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 4) of
    0 : a[i]:=1;
    1 : a[i]:=7;
    2 : a[i]:=9;
    3 : a[i]:=3;
   end;
   i:=i*7;
  end; i:=c; end;


 i:=-1;
 while i<1000 do Begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 2) of
    0 : a[i]:=1;
    1 : a[i]:=9;
   end;
   i:=i*9;
  end; i:=c; end;


 i:=-6;
 while i<1000 do Begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 2) of
    0 : a[i]:=6;
    1 : a[i]:=4;
   end;
   i:=i*4;
  end; i:=c; end;

   i:=-2;
 while i<1000 do Begin
   i:=i+10; c:=i; j:=0;
 while i<=1000 do
  Begin
   inc(j); u[i]:=true;
   case (i*j mod 4) of
    0 : a[i]:=6;
    1 : a[i]:=8;
    2 : a[i]:=4;
    3 : a[i]:=2;
   end;
   i:=i*8;
  end; i:=c; end;

  for i:=2 to 20 do
  a[i]:=(a[i]+a[i-1]) mod 10;
                {
  for i:=1 to 250 do
  begin write(a[i],' ');
  if i mod 20=0 then writeln ; end;

               }

  readln(t);
  for i:=1 to t do
  begin
    readln(s);
    if length(s)=1 then writeln(a[ord(s[1])-48])
                   else
                          writeln(a[ord(s[length(s)-1])*10+ord(s[length(s)]) mod 20]);
                         end;




  close(output);
  close(input);
end.