var
   n: integer;
begin
end;

macro '[c]change values';
begin
    changevalues(255,255,n);
    killRoi;
    showmessage('n = ',n);
end;

macro '[s]set mark value';
begin
   n := getNumber('n',n+1);
   showmessage('n = ',n);
end;

macro '[h]next mark';
begin
  n := n + 1;
   showmessage('n = ',n);
end;

macro '[g]prev mark';
begin
   n := n - 1;
   showmessage('n = ',n);
end;