program ultimaCifra;

var
  pc:integer;
  uc:integer;
  f,g:text;
  i,t:integer;
  s:string;
  aux:integer;
  v : array[0..99] of integer;

function putere(x,pow:integer):integer;
var
  xc,t:integer;
begin
  xc := x;
  for t:=2 to pow do
      xc := (xc * x) mod 10;
  putere := xc;
end;

begin
  v[0]:= 0;

  for i:=1 to 99 do
    v[i]:=(v[i-1] + putere(i mod 10, i)) mod 10;
    
    
    


  assign(f,'cifra.in');
  reset(f);
  assign(g,'cifra.out');
  rewrite(g);

  uc := 0;
  read(f,t);

  for i:=1 to t do begin
     readln(f);
     read(f,s);

     val(s[length(s)], uc, aux);
     
     if length(s)> 1 then
        val(s[length(s)-1], pc, aux)
     else
        pc := 0;
     writeln(g, v[pc*10+uc]);
  end;
  close(g);
  close(f);
end.