股票投資

import java.util.Scanner;

public class calculate4 {

    public static void main(String[] args) {
        // TODO 自動生成的方法存根
        Scanner scanner = new Scanner(System.in);
        System.out.println("複利電腦：計算複利和單利終值請按1,計算本金請按2；股票投資：計算時間請按3，計算報酬率請按4，計算資産總值請按5" );
        int num=scanner.nextInt();
        if (num == 1) {
            double N = 1, sum;
            System.out.print("請輸入本金：");
            double money = scanner.nextDouble();
            System.out.print("請輸入存錢年數：");
            int years = scanner.nextInt();
            System.out.print("請輸入利率：");
            double r = scanner.nextDouble();
            sum = money + money * years * r;
            System.out.println("單利終值為：" + sum);
            sum = 0;
            for (int i = 1; i <= years; i++) {
                N = (1 + r) * N;
            }
            sum = N * money;
            System.out.println("複利終值為：" + sum);

        }
        if (num == 2) {
            double N = 1, money;
            System.out.print("請輸入複利終值：");
            double sum = scanner.nextDouble();
            System.out.print("請輸入存錢年數：");
            int years = scanner.nextInt();
            System.out.print("請輸入利率：");
            double r = scanner.nextDouble();
            for (int i = 1; i <= years; i++) {
                N = (1 + r) * N;
            }
            money = sum / N;
            System.out.println("應投入的本金為：" + money);
        }
        if (num == 3) {
            double years;
            System.out.print("請輸入本金：");
            double money = scanner.nextDouble();
            System.out.print("請輸入最後得到資産總值：");
            double sum = scanner.nextDouble();
            System.out.print("請輸入利率：");
            double r = scanner.nextDouble();        
            years = sum / (money * r);
            System.out.println("時間為（年）：" + years);
        }
        if (num == 4) {
            double r;
            System.out.print("請輸入本金：");
            double money = scanner.nextDouble();
            System.out.print("請輸入最後得到資産總值：");
            double sum = scanner.nextDouble();
            System.out.print("請輸入存錢年數：");
            int years = scanner.nextInt();
            r=sum/(money*years);
            System.out.println("利率為：" + r);
        }
        if (num == 5){
            double sum;
            System.out.print("請輸入本金：");
            double money = scanner.nextDouble();
            System.out.print("請輸入利率：");
            double r = scanner.nextDouble();
            System.out.print("請輸入存錢年數：");
            int years = scanner.nextInt();
            sum=money*r*years;
            System.out.println("若投資本金每年固定不變，則最後得到的資産總值為：" + sum);
            sum=0;
            for(int i=1;i<=years;i++){
                sum=money*r*1;
                money=sum;                
            }
            System.out.println("若連本帶利投資，則最後得到的資産總值為：" + sum);
        }
    }
}      

本次程式的功能是你可以自由選擇你想要計算的功能，如：計算股票投資的資産總值、報酬率和時間，

選擇之後便會出現相應的資料讓使用者填寫，最後使用者便可以得到自己想要的結果。