Всем привет! Помогите пожалуйста доработать код, необходимо чтобы решение должно содержало метод calc внутри класса Main.

Метод должен принимать строку и возвращать строку import java.util.*; //решение должно содержать данный класс class Main { public static String[] calc(String inputString) { String[] calc_inputString = inputString.split(" "); if (calc_inputString.length != 3) { Scanner inputString_a_value_again = new Scanner(System.in); System.out.println("Неверный формат ввода данных. Введите выражение, разделяя каждый символ _пробелом_"); inputString = inputString_a_value_again.nextLine(); return calc(inputString); } else { return calc_inputString; } } private static boolean its_an_arabic_numbers = true; public static void main(String[] args) { Scanner inputString_a_value = new Scanner(System.in); System.out.print("Введите выражение(Числа от 1 до 10): "); String inputString = inputString_a_value.nextLine(); while (!inputString.isEmpty()) { String[] calc_inputString; calc_inputString = calc(inputString); String operation = calc_inputString[1]; Number values; int value1 = 0; int value2 = 0; // Переводим в int. Если введены римские, выкинет исключение try { value1 = Integer.parseInt(calc_inputString[0]); value2 = Integer.parseInt(calc_inputString[2]); //values = new Arabic(value1, value2, 0); } catch (NumberFormatException e) { its_an_arabic_numbers = false; System.out.println("Введены римские цифры"); //values = new Romes(parsed_input[0], parsed_input[2], 0); } if (its_an_arabic_numbers) { values = new Arabic(value1, value2); } else { values = new Romes(calc_inputString[0], calc_inputString[2]); } if (operation.equals("+")) { values.sum(); } else if (operation.equals("-")) { values.sub(); } else if (operation.equals("/") || operation.equals(":")) { values.div(); } else if (operation.equals("*") || operation.equals("x")) { values.mul(); } if (its_an_arabic_numbers) { System.out.println("Ответ: " + values.getResult()); } else { System.out.println("Ответ: " + values.getStringResult()); } System.out.println(); System.out.print("Введите следующее выражение: "); inputString = inputString_a_value.nextLine(); } System.out.println("Вы вышли из калькулятора"); } } abstract class Number { public abstract void sum(); public abstract void sub(); public abstract void div(); public abstract void mul(); public abstract int getResult(); public abstract String getStringResult(); } class Romes extends Number { private String romes_value1; private String romes_value2; private int romes_value1_int; private int romes_value2_int; private int result_int; private String sign = ""; private String result_string; private final String[] roman_letters_9 = {"I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"}; Romes(String value1, String value2) { this.romes_value1 = value1; this.romes_value2 = value2; this.romes_value1_int = convert_to_int(romes_value1); this.romes_value2_int = convert_to_int(romes_value2); } private String convert_result_to_Romes(int n, int ostatok) { ostatok = n % 10; if (ostatok != 0) { try { return convert_result_to_Romes(n - ostatok, 0) + roman_letters_9[ostatok - 1]; } catch (ArrayIndexOutOfBoundsException e) { sign = "-"; return convert_result_to_Romes(n - ostatok, 0) + roman_letters_9[(ostatok + 1) * -1]; } } //Возможность вывести отрицательное римское число if (n > 0) { n = n - 10; return convert_result_to_Romes(n,0) + "X"; } else if (n < 0) { n = n + 10; return convert_result_to_Romes(n,0) + "X"; } else { return sign; } } @Override public void sum() { result_int = romes_value1_int + romes_value2_int; result_string = convert_result_to_Romes(result_int, result_int); } @Override public void sub() { result_int = romes_value1_int - romes_value2_int; result_string = convert_result_to_Romes(result_int, result_int); } @Override public void div() { try { result_int = romes_value1_int / romes_value2_int; result_string = convert_result_to_Romes(result_int, result_int); } catch (ArithmeticException e) { System.out.print("Проверьте правильность ввода римских цифр. Вероятно введены и арабские и римские одновременно. "); return; } } @Override public void mul() { result_int = romes_value1_int * romes_value2_int; result_string = convert_result_to_Romes(result_int, result_int); } @Override public int getResult() { return result_int; } public String getStringResult() { return result_string; } private int convert_to_int(String romes_value){ char[] value_char = romes_value.toCharArray(); int[] values_int = new int[value_char.length]; for (int i = 0; i < value_char.length; i++) { switch (value_char[i]) { case 'I': values_int[i] = 1; break; case 'V': values_int[i] = 5; break; case 'X': values_int[i] = 10; break; default: System.out.println("Содержится неверный символ. Проверьте правильность ввода римских цифр:" + "\n" + "I = 1" + "\n" + "V = 5" + "\n" + "X = 10"); break; } } int result = values_int[0]; for (int i = 0; i < values_int.length && values_int.length > i + 1; i++) { if (values_int[i] >= values_int[i+1]) { result += values_int[i+1]; } else if (values_int[i] < values_int[i+1]) { result = result + values_int[i+1] - 2; } } return result; } public String getRomes_value1() { return romes_value1; } public String getRomes_value2() { return romes_value2; } public void setRomes_value1(String romes_value1) { this.romes_value1 = romes_value1; } public void setRomes_value2(String romes_value2) { this.romes_value2 = romes_value2; } public int getRomes_value1_int() { return romes_value1_int; } public int getRomes_value2_int() { return romes_value2_int; } public void setRomes_value1_int(int romes_value1_int) { this.romes_value1_int = romes_value1_int; } public void setRomes_value2_int(int romes_value2_int) { this.romes_value2_int = romes_value2_int; } } class Arabic extends Number { private int value1; private int value2; private int result; Arabic(int value1, int value2) { this.value1 = value1; this.value2 = value2; } public void sum() { this.result = value1 + value2; } public void sub() { this.result = value1 - value2; } public void div() { try{ this.result = value1 / value2; } catch (ArithmeticException e) { System.out.print("Деление на 0! "); return; } } public void mul() { this.result = value1 * value2; } @Override public int getResult() { return result; } @Override public String getStringResult() { return "" + result; } public int getValue1() { return value1; } public int getValue2() { return value2; } public void setResult(int result) { this.result = result; } public void setValue1(int value1) { this.value1 = value1; } public void setValue2(int value2) { this.value2 = value2; } }