股票投资

import java.util.Scanner;

public class calculate4 {

    public static void main(String[] args) {
        // TODO 自动生成的方法存根
        Scanner scanner = new Scanner(System.in);
        System.out.println("复利计算器：计算复利和单利终值请按1,计算本金请按2；股票投资：计算时间请按3，计算报酬率请按4，计算资产总值请按5" );
        int num=scanner.nextInt();
        if (num == 1) {
            double N = 1, sum;
            System.out.print("请输入本金：");
            double money = scanner.nextDouble();
            System.out.print("请输入存钱年数：");
            int years = scanner.nextInt();
            System.out.print("请输入利率：");
            double r = scanner.nextDouble();
            sum = money + money * years * r;
            System.out.println("单利终值为：" + sum);
            sum = 0;
            for (int i = 1; i <= years; i++) {
                N = (1 + r) * N;
            }
            sum = N * money;
            System.out.println("复利终值为：" + sum);

        }
        if (num == 2) {
            double N = 1, money;
            System.out.print("请输入复利终值：");
            double sum = scanner.nextDouble();
            System.out.print("请输入存钱年数：");
            int years = scanner.nextInt();
            System.out.print("请输入利率：");
            double r = scanner.nextDouble();
            for (int i = 1; i <= years; i++) {
                N = (1 + r) * N;
            }
            money = sum / N;
            System.out.println("应投入的本金为：" + money);
        }
        if (num == 3) {
            double years;
            System.out.print("请输入本金：");
            double money = scanner.nextDouble();
            System.out.print("请输入最后得到资产总值：");
            double sum = scanner.nextDouble();
            System.out.print("请输入利率：");
            double r = scanner.nextDouble();        
            years = sum / (money * r);
            System.out.println("时间为（年）：" + years);
        }
        if (num == 4) {
            double r;
            System.out.print("请输入本金：");
            double money = scanner.nextDouble();
            System.out.print("请输入最后得到资产总值：");
            double sum = scanner.nextDouble();
            System.out.print("请输入存钱年数：");
            int years = scanner.nextInt();
            r=sum/(money*years);
            System.out.println("利率为：" + r);
        }
        if (num == 5){
            double sum;
            System.out.print("请输入本金：");
            double money = scanner.nextDouble();
            System.out.print("请输入利率：");
            double r = scanner.nextDouble();
            System.out.print("请输入存钱年数：");
            int years = scanner.nextInt();
            sum=money*r*years;
            System.out.println("若投资本金每年固定不变，则最后得到的资产总值为：" + sum);
            sum=0;
            for(int i=1;i<=years;i++){
                sum=money*r*1;
                money=sum;                
            }
            System.out.println("若连本带利投资，则最后得到的资产总值为：" + sum);
        }
    }
}