(Program
{ (Equal
  {-(Identifier)-}
  {-(Identifier)-})
->(Comparison
  {+(Identifier)+}
  {+(Identifier)+}) }
{+(Matches
  {+(Identifier)+}
  {+(Identifier)+})+}
{+(Assignment
  {+(Identifier)+}
  {+(Not
    {+(Identifier)+})+})+}
{-(Not
  {-(Equal
    {-(Identifier)-}
    {-(Identifier)-})-})-}
{-(Equal
  {-(Identifier)-}
  {-(Identifier)-})-})