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