0317复利计算3.0

import java.util.Scanner;

public class text {
    public static void main(String[] args) {
        

        do {
            Scanner scanner = new Scanner(System.in);
            System.out.println(" ");
            System.out.print("请选择（0为退出，1为算本息，2为算本金，3为算投资，4为算n年后资产总值）：");
            int number1 = scanner.nextInt();

            if (number1 == 1) {
                System.out.print("请输入本金：");
                double money = scanner.nextDouble();
                System.out.print("请输入年利率：");
                double rate = scanner.nextDouble();
                System.out.print("请输入年限：");
                int year = scanner.nextInt();
                
                System.out.print("请选择（1为复利计算，2为单利计算）：");
                int number2 = scanner.nextInt();
                
                if (number2 == 1) {
                    for (int i = 1; i <= year; i++) {
                        money = (1 + rate) * money;
                    }
                    System.out.println("存入" + year + "年后的复利计算本息为：" +(double) (Math.round(money*100)/100.0));
                    
                }
                if (number2 == 2) {
                    money = money + money * rate * year;
                    System.out.println("存入" + year + "年后的单利计算本息为：" +(double) (Math.round(money*100)/100.0));
                }
                
                

            }

            if (number1 == 2) {
                System.out.print("请输入本息：");
                double money = scanner.nextDouble();
                System.out.print("请输入年利率：");
                double rate = scanner.nextDouble();
                System.out.print("请输入年限：");
                int year = scanner.nextInt();
                
                System.out.print("请选择（1为复利计算，2为单利计算）：");
                int number2 = scanner.nextInt();
                
                if (number2 == 1) {
                    double num = 1;
                    for (int i = 1; i <= year; i++) {
                        num = num * (1 + rate);
                    }
                    money = money * (1 / num);
                    System.out.println("复利计算需要存入的本金为：" +(double) (Math.round(money*100)/100.0));
                }
                if (number2 == 2) {
                    money = money * (1 / (1 + rate * year));
                    System.out.println("单利计算需要存入的本金为：" + (double) (Math.round(money*100)/100.0));
                }

            }
            if (number1 == 3) {

                System.out.print("请输入投资金额：");
                double money1 = scanner.nextDouble();
                System.out.print("请输入收获金额：");
                double money2 = scanner.nextDouble();

                System.out.print("请选择（1为算时间，2为算利率）：");
                int number2 = scanner.nextInt();
                
                if (number2 == 1) {
                    System.out.print("请输入年利率：");
                    double rate = scanner.nextDouble();
                    double year;
                    year = Logarithm.log(money2/money1,1+rate);
                    year = Math.ceil(year);
                    System.out.println("需要存入的年限为：" + year);
                } else if (number2 == 2) {
                    System.out.print("请输入年限：");
                    int year = scanner.nextInt();
                    double rate;
                    rate = Math.pow(money2/money1, 1.0/year)-1;
                    System.out.println("所需年利率为：" + (double) (Math.round(rate*10000)/10000.0));
                }
            }
            
            if(number1 == 4){
                System.out.print("请输入每年的投资金额：");
                double money1 = scanner.nextDouble();
                System.out.print("请输入年利率：");
                double rate = scanner.nextDouble();
                System.out.print("请输入年限：");
                int year = scanner.nextInt();double money2=0;
                for(int i=1;i<=year;i++){
                    
                    money1=money1+money2;
                    money2=money1*(1+rate);
                    
                }
                System.out.println(year+"年后的资产总值为：" + (double) (Math.round(money2*100)/100.0));
            }

            if (number1 == 0) {
                System.out.println("谢谢使用！" );
                System.exit(0);
                
            }
        } while (true);
    }
}

public class Logarithm {
    static public double log(double value, double base){
        return Math.log(value)/Math.log(base);
         
     }

}