노재경_homework8.java

//노재

import java.util.Scanner;

public class Main{
    static final int[] TAX_BRACKETS = {12000000, 46000000, 88000000, 150000000, 300000000, 500000000, 1000000000}; //과세 구간별 기준
    static final double[] TAX_RATES = {0.06, 0.15, 0.24, 0.35, 0.38, 0.40, 0.42, 0.45}; //구간별 세율
    static final int[] DEDUCTIONS = {0, 1080000, 5220000, 14900000, 19400000, 25400000, 35400000, 65400000}; //공제액

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("연소득을 입력해 주세요: ");
        int income = scanner.nextInt();
        scanner.close();

        int taxbyrate = calculateTaxRate(income);
        int taxbydeduction = calculateTaxDeduction(income);

        System.out.println("[세율에 의한 세금]: " + taxbyrate);
        System.out.println("[누진공제 계산에 의한 세금]: " + taxbydeduction);
    }

    public static int calculateTaxRate(int income) {
        int taxbyrate = 0;

        int prevBracket = 0;

        for (int i = 0; i < 7; i++) {
            if (income > TAX_BRACKETS[i]) {
                taxbyrate += (TAX_BRACKETS[i] - prevBracket) * TAX_RATES[i];
                prevBracket = TAX_BRACKETS[i];
            } else {
                taxbyrate += (income - prevBracket) * TAX_RATES[i];
                break;
            }
        }
        return taxbyrate;
    }
    
    public static int calculateTaxDeduction(int income){
        int taxbydeduction = 0;

        taxbydeduction += (int) (income * TAX_RATES[getBracketIndex(income)] - DEDUCTIONS[getBracketIndex(income)]);
        return taxbydeduction;
        
    }

    public static int getBracketIndex(int income) {
        for (int i = 0; i < TAX_BRACKETS.length; i++) {
            if (income <= TAX_BRACKETS[i]) {
                return i;
            }
        }
        return TAX_BRACKETS.length;
    }
}