public static void main ( String [ ] args ) {
  push ( head , 7 ) ;
  push ( head , 6 ) ;
  push ( head , 8 ) ;
  push ( head , 4 ) ;
  push ( head , 1 ) ;
  System . out . println ( "Sum of nodes = " + sumOfNodes ( head ) ) ;
}

public static void main ( String [ ] args ) { push ( head , 7 ) ; push ( head , 6 ) ; push ( head , 8 ) ; push ( head , 4 ) ; push ( head , 1 ) ; System . out . println ( " Sum ▁ of ▁ nodes ▁ = ▁ " + sumOfNodes ( head ) ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) body: (block (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (decimal_integer_literal)))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (decimal_integer_literal)))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (decimal_integer_literal)))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (decimal_integer_literal)))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (decimal_integer_literal)))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (binary_expression left: (string_literal) right: (method_invocation name: (identifier) arguments: (argument_list (identifier)))))))))