var t,a,b:longint;
function ud(x:longint):longint;
  var i,p,q,k:longint;
  begin
    i:=0;p:=x;q:=0;
    while p>0 do begin
      inc(i);
      k:=p;
      p:=p div 10;
      q:=q*10+k-p*10;
    end;
    exit(q);
  end;
begin
  readln(t);
  while t>0 do begin
    dec(t);
    readln(a,b);
    writeln(ud(ud(a)+ud(b)));
  end;
end.