(Statements
{+(Assignment
  {+(Identifier)+}
  {+(If
    {+(Identifier)+}
    {+(Identifier)+}
    {+(Identifier)+})+})+}
  (If
  { (Identifier)
  ->(Identifier) }
    (Call
      (Identifier)
      (Empty))
  { (Identifier)
  ->(Call
    {+(Identifier)+}
    {+(Empty)+}) })
{-(Assignment
  {-(Identifier)-}
  {-(If
    {-(Identifier)-}
    {-(Identifier)-}
    {-(Identifier)-})-})-})