import java.util.Scanner;
public class compounding {
public static void main(String[] args) {
menu();
int m = scanner.nextInt();
switch(m)
{
case 1:
compound_calate(); break;
case 2:
single_calate();break;
}
}
private static void compound_calate() {//复利计算
while (true) {
System.out.println("");
menu1();
int n = scanner.nextInt();
if (n >= 0 && n <= 6) {
if (n == 0)
System.exit(0);
switch (n) {
case 1:
principal();
break;
case 2:
compound_final();
break;
case 3:
time();
break;
case 4:
annual_interest_rate();
break;
case 5:
equal_investment();
break;
case 6:
Average_repayment();
break;
}
} else {
System.out.println("输入超出范围，请重新输入:");
}
}
}
static Scanner scanner = new Scanner(System.in);
static void menu()// 功能介绍函数
{
System.out.printf("\t\t|******************************************************|\n");
System.out.printf("\t\t| 利息计算系统 |\n");
System.out.printf("\t\t|******************************************************|\n");
System.out.printf("\t\t| 1: 复利计算 |\n");
System.out.printf("\t\t| 2: 单利计算 |\n");
System.out.printf("\t\t|******************************************************|\n");
System.out.printf("\t请选择<1~2>:");
}
static void menu1()// 菜单
{
System.out.printf("\t\t|******************************************************|\n");
System.out.printf("\t\t| 1: 本金计算 |\n");
System.out.printf("\t\t| 2: 终值计算 |\n");
System.out.printf("\t\t| 3: 期数计算 |\n");
System.out.printf("\t\t| 4: 利率计算 |\n");
System.out.printf("\t\t| 5: 定期计算 |\n");
System.out.printf("\t\t| 6: 等额本息还款 |\n");
System.out.printf("\t\t|******************************************************|\n");
System.out.printf("请输入你要选择的功能(1~6):");
}
static double principal_formula(double S, double i, int Year)// 本金计算公式
{
double P;
P = S/ Math.pow((1 + i ), Year);
return P;
}
static void principal()// 计算本金
{
int Year;
double i,P,S;
System.out.printf("输入期待复利终值:");
S = scanner.nextDouble();
System.out.printf("年利率:");
i = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
P = principal_formula(S, i, Year);
System.out.println("年复利终值为" + S + "需要本金为:" + P);
}
static double compound_amount_formula(double P, double i, int Year)// 复利计算公式
{
double F;
F = P * Math.pow((1 + i ),Year);
return F;
}
static void compound_final()// 计算复利终值
{
int Year;
double i, F, P;
System.out.printf("请输入本金：");
P = scanner.nextDouble();
System.out.printf("请输入年利率：");
i = scanner.nextDouble();
System.out.printf("请输入复利次数（年）：");
Year = scanner.nextInt();
F = compound_amount_formula(P, i, Year);
System.out.println("复利终值:" + F);
}
static double single_interest_formula(double P, int Year, double i)// 单利计算公式
{
double F;
F = P *(1+i*Year);
return F;
}
static void single_calate()// 单利计算
{
int Year;
double i, F, P;
System.out.printf("存入本金:");
P = scanner.nextDouble();
System.out.printf("年利率:");
i = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
F = single_interest_formula(P, Year, i);
System.out.println("本息和为:" + F);
}
static int years_formula(double F, double P, double i)// 根据复利终值求年份
{
int year;
year = (int) (Math.log(F / P) / Math.log(1 + i ));
return year;
}
static void time()// 求年份
{
int Year;
double i, F, P;
System.out.printf("复利终值:");
F = scanner.nextDouble();
System.out.printf("存入本金:");
P = scanner.nextDouble();
System.out.printf("年利率:");
i = scanner.nextDouble();
Year= years_formula(F, P, i);
System.out.println("从" + P + "到" + F + "需要" + Year+ "年");
}
static double rate_formula(double F, double P, int Year)// 复利的利率计算公式
{
double rate;
rate = (Math.pow(F / P, 1.0 / Year) - 1);
return rate;
}
static void annual_interest_rate()// 计算年利率
{
int Year;
double i, F, P;
System.out.printf("复利终值:");
F = scanner.nextDouble();
System.out.printf("存入本金:");
P = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
i = rate_formula(F, P, Year);
System.out.println("从" + P + "到" + F + "需要" + i);
}
static double equal_investment_years(double P, int Year, double i)// 按照年份等额投资计算公式
{
double final_value;
final_value = P * (Math.pow(1 + i, Year) - 1) / i;
return final_value;
}
static double equal_investment_months(double P, int Year, double i)// 按照月份等额投资计算公式
{
double final_value;
final_value = P * 12 * (1 + i) * (Math.pow(1 + i, Year) - 1) / i;
return final_value;
}
static void equal_investment()// 计算等额投资
{
int Year, n;
double i, F, P;
System.out.printf("\t\t1:按年投资\n\t\t2:按月投资\n");
System.out.printf("请选择你要的功能<1|2>:");
n = scanner.nextInt();
if (n == 1) {
System.out.printf("存入本金:");
P = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
System.out.printf("年利率:");
i = scanner.nextDouble();
F = equal_investment_years(P, Year, i);
System.out.println(Year+ "年后的总产值:" + F);
} else if (n == 2) {
System.out.printf("存入本金:");
P = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
System.out.printf("月利率:");
i = scanner.nextDouble();
F = equal_investment_months(P, Year, i);
System.out.println(Year + "年后的总产值:" + F);
} else {
System.out.printf("输入有误!\n");
}
}
static double equal_repayment_formula(double F, int Year,double i)// 等额还款公式
{
double refund;
refund = F * i / (12 * (1 + i) * (Math.pow(1 + i, Year) - 1));
return refund;
}
static void Average_repayment()// 等额还款
{
int Year;
double i, F, P;
System.out.printf("贷款金额:");
F = scanner.nextDouble();
System.out.printf("存入年限:");
Year = scanner.nextInt();
System.out.printf("年利率:");
i = scanner.nextDouble();
P = equal_repayment_formula(F, Year, i);
System.out.println("贷款" + F + "每月需要还款" + P);
}
}