(Program
{ (LessThanEqual
  {-(Send
    {-(Identifier)-})-}
  {-(Send
    {-(Identifier)-})-})
->(LessThan
  {+(Send
    {+(Identifier)+})+}
  {+(Send
    {+(Identifier)+})+}) }
{+(GreaterThan
  {+(Send
    {+(Identifier)+})+}
  {+(Send
    {+(Identifier)+})+})+}
{-(GreaterThanEqual
  {-(Send
    {-(Identifier)-})-}
  {-(Send
    {-(Identifier)-})-})-})