import java.util.Scanner;public class Calculate5 {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;"+ "银行贷款：计算月等额还款金额请按6" );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=((Math.log(sum)/Math.log(1+r))-(Math.log(money)/Math.log(1+r)));System.out.println("时间为（年）：" + years);}if (num == 4) {double r,N;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();N=Math.pow(sum/money, 1d/years);//1d是开根号，没有1d就是多少次方r=N-1;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=years*12*(money*(r/12)+money);System.out.println("若投资本金每月固定不变，则最后得到的资产总值为：" + sum);sum=0;sum=money*(Math.pow(1+r,years)-1)/r;System.out.println("若连本带利投资，则最后得到的资产总值为：" + sum);}if(num==6){double sum,k;int month;System.out.print("请输入本金：");double money = scanner.nextDouble();System.out.print("请输入年利率：");double r = scanner.nextDouble();System.out.print("请输入贷款年数：");int years = scanner.nextInt();k=r/12;//k为月利率month=years*12;//month为贷款月数sum=money*k*Math.pow(1+k, month)/(Math.pow(1+k,month)-1);System.out.println("每月等额还款金额为："+sum);}if(num<1||num>6){System.out.println("输入有误，请重新输入");}}
}