final public sum_AST SumExpression() throws ParseException {
  factor_AST lhs = null;
  Token sign = null;
  sum_AST rhs = null;
    sum_AST jjtn001 = new sum_AST(JJTSUM_AST);
    boolean jjtc001 = true;
    jjtree.openNodeScope(jjtn001);
    try {
      lhs = FactorExpression();
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case PLUS:
      case MINUS:
        switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
        case PLUS:
          sign = jj_consume_token(PLUS);
          rhs = SumExpression();
          break;
        case MINUS:
          sign = jj_consume_token(MINUS);
          rhs = SumExpression();
          break;
        default:
          jj_la1[52] = jj_gen;
          jj_consume_token(-1);
          throw new ParseException();
        }
        break;
      default:
        jj_la1[53] = jj_gen;
        ;
      }
    jjtree.closeNodeScope(jjtn001, jjtree.nodeArity() > 1);
    jjtc001 = false;
    jjtn001.lhs = lhs;
    jjtn001.rhs = rhs;
    jjtn001.sign = sign;
    {if (true) return jjtn001;}
    } catch (Throwable jjte001) {
    if (jjtc001) {
      jjtree.clearNodeScope(jjtn001);
      jjtc001 = false;
    } else {
      jjtree.popNode();
    }
    if (jjte001 instanceof RuntimeException) {
      {if (true) throw (RuntimeException)jjte001;}
    }
    if (jjte001 instanceof ParseException) {
      {if (true) throw (ParseException)jjte001;}
    }
    {if (true) throw (Error)jjte001;}
    } finally {
    if (jjtc001) {
      jjtree.closeNodeScope(jjtn001, jjtree.nodeArity() > 1);
    }
    }
    throw new Error("Missing return statement in function");
  }