static int add ( int x , int y ) {
  while ( y > 0 && y != 0 ) {
    x ++ ;
    y -- ;
  }
  while ( y < 0 && y != 0 ) {
    x -- ;
    y ++ ;
  }
  return x ;
}

static int add ( int x , int y ) { while ( y > 0 && y != 0 ) { x ++ ; y -- ; } while ( y < 0 && y != 0 ) { x -- ; y ++ ; } return x ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier)) (formal_parameter type: (integral_type) name: (identifier))) body: (block (while_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) body: (block (expression_statement (update_expression (identifier))) (expression_statement (update_expression (identifier))))) (while_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) body: (block (expression_statement (update_expression (identifier))) (expression_statement (update_expression (identifier))))) (return_statement (identifier))))