program cifre;
const u:array[0..1,1..9]of byte = ((1,5,2,8,3,9,2,8,7),(1,7,0,6,1,7,4,8,7));
var n,z:byte;
    t,j,er:word;
    f,g:text;
    m:0..1;
    l:string[101];
begin
 assign(f,'cifra.in');reset(f);assign(g,'cifra.out');rewrite(g);
 readln(f,t);
 for j:=1 to t do
  begin
   readln(f,l);
   l:='0'+l;
   val(copy(l,length(l),1),n,er);
   val(copy(l,length(l)-1,1),z,er);
   m:=z and 1;
   writeln(g,(((z*7)mod 10)+u[m,n])mod 10);
  end;
 close(f);close(g);
end.