/**
 * 用接口给一个有工资收入和稿费收入的小伙伴算税
 */
public class Main {

	public static void main(String[] args) {
		// TODO: 用接口给一个有工资收入和稿费收入的小伙伴算税:
		Income[] incomes = new Income[] {  new SalaryIncome(7500), new RoyaltyIncome(12000) };
		double total = 0;
		for (Income income:incomes) {
			total+=income.getTax();
		}
		System.out.println(total);
	}
}


/**
 * 稿费收入税率是20%
 */
public class RoyaltyIncome implements Income{
    private double income;

    public RoyaltyIncome(double income){
        this.income = income;
    }
    @Override
    public double getTax() {
        return income * 0.2;
    }
}


/**
 * 工资收入
 */
public class SalaryIncome implements Income{
    private double income;

    public SalaryIncome(double income){
        this.income = income;
    }
    @Override
    public double getTax() {
        if (income>=5000){
            return (income-5000)*0.2;
        }else
            return 0;
    }
}