자바의 신 - 여러 종류의 연산자

public class SalaryManager {
    public static void main(String[]args){
        SalaryManager yumin = new SalaryManager();
        System.out.println("세후 연봉 = "+yumin.getMonthlySalary(20000000));
    }
    public double getMonthlySalary(int yearlySalary){
        double monthlySalary= yearlySalary/12.0;
        
        double a=calculateTax(monthlySalary);
        double b=calculateNationalPension(monthlySalary);
        double c=calculateHealthInsurance(monthlySalary);
        double totalTax=a+b+c;
        monthlySalary-=totalTax;
        return monthlySalary;
        }
    public double calculateTax(double monthlySalary){
            double calculateTax=( monthlySalary * 0.125);
        System.out.println("근로 소득세 ="+calculateTax);
        return (calculateTax);
    }
    public double calculateNationalPension(double monthSalary){
        double nationalPension=( monthSalary * 0.081);
        System.out.println("국민 연금 ="+nationalPension);
        return (nationalPension);
    }
    public double calculateHealthInsurance(double monthSalary){
        double healthInsurance=( monthSalary * 0.135);
        System.out.println("건강 보험료 ="+healthInsurance);
        return (healthInsurance);
    }
}