RomanNumeralConverter

public static void main(String[] args) {

        System.out.println("Please enter an equation like the following:\nOperand1 operator Operand2");
        Scanner in = new Scanner(System.in);
        String ara = in.nextLine();
        int fin;
        String[] tokens = ara.split(" ");

        switch(tokens[1]){
        case "+":
            fin = Integer.parseInt(tokens[0]) + Integer.parseInt(tokens[2]);
            System.out.println(mar13.RomanCalc(Integer.parseInt(tokens[0])) + " + " + mar13.RomanCalc(Integer.parseInt(tokens[2])) + " = " + mar13.RomanCalc(fin));
            break;
        case "-":
            fin = Integer.parseInt(tokens[0]) - Integer.parseInt(tokens[2]);
            System.out.println(mar13.RomanCalc(Integer.parseInt(tokens[0])) + " - " + mar13.RomanCalc(Integer.parseInt(tokens[2])) + " = " + mar13.RomanCalc(fin));
            break;
        case "*":
            fin = Integer.parseInt(tokens[0]) * Integer.parseInt(tokens[2]);
            System.out.println(mar13.RomanCalc(Integer.parseInt(tokens[0])) + " * " + mar13.RomanCalc(Integer.parseInt(tokens[2])) + " = " + mar13.RomanCalc(fin));
            break;
        case "/":
            fin = Integer.parseInt(tokens[0]) / Integer.parseInt(tokens[2]);
            System.out.println(mar13.RomanCalc(Integer.parseInt(tokens[0])) + " / " + mar13.RomanCalc(Integer.parseInt(tokens[2])) + " = " + mar13.RomanCalc(fin));
            break;
        }
        in.close();

    }

public static String RomanCalc(int ara) {

        String[] ONES = {"I","II","III","IV","V","VI","VII","VIII","IX"};
        String[] TENS = {"X","XX","XXX","XL","L","LX","LXX","LXXX","XC"};
        String[] HUNDREDS = {"C","CC","CCC","CD","D","DC","DCC","DCCC","DM"};
        String[] THOUSANDS = {"M","MM","MMM"};

        int ones = ara%10;
        ara = (ara-ones)/10;
        int tens = ara%10;
        ara = (ara-tens)/10;
        int hundreds = ara%10;
        ara = (ara - hundreds)/10;
        int thousands = ara%10;

        String fin="";
        if(thousands >= 1){
            fin += THOUSANDS[thousands - 1];
        }
        if(hundreds >= 1){
            fin += HUNDREDS[hundreds - 1];
        }
        if(tens >=1){
            fin += TENS[tens - 1];
        }
        if(ones >= 1){
            fin+= ONES[ones - 1];
        }
        return fin;

    }