0317复利计算3.0

package kxj;
import java.util.Scanner;

public class Fulijisuan {
public static double p,i,f ;
public static double n;

//计算本金
public static void Benjin(){
//int n;
//float f,i,p;
Scanner scanner=new Scanner(System.in);
System.out.println("请输入终值: ");
f=scanner.nextDouble();
System.out.println("请输入年利率: ");
i=scanner.nextDouble();
System.out.println("请输入年数: ");
n=scanner.nextInt();
p=(float) (f*1/Math.pow(1+i, n));
System.out.println("本金为： "+(double)(Math.round(p*100)/100.0));

}

//计算本息和
public static void Benxihe(){
double sum1,sum2;
Scanner scanner=new Scanner(System.in);
System.out.println("请输入本金: ");
p=scanner.nextDouble();
System.out.println("请输入年利率: ");
i=scanner.nextDouble();
System.out.println("请输入年数: ");
n=scanner.nextInt();
sum1=(float) (p*Math.pow(1+i, n));
sum2=p*(1+i*n);
System.out.println("复利的本息和为： "+(double)(Math.round(sum1*100)/100.0));
System.out.println("单利的本息和为： "+(double)(Math.round(sum2*100)/100.0));
}

//计算年数
public static void Nianshu(){
Scanner scanner=new Scanner(System.in);
System.out.println("请输入本金: ");
p=scanner.nextDouble();
System.out.println("请输入终值: ");
f=scanner.nextDouble();
System.out.println("请输入年利率: ");
i=scanner.nextDouble();
n=Logarithm.log(f/p,1+i);
n=Math.ceil(n);
System.out.println("需要存的年数为: "+Math.ceil(n));
}

//计算年利率
public static void Lilv(){
Scanner scanner=new Scanner(System.in);
System.out.println("请输入本金: ");
p=scanner.nextDouble();
System.out.println("请输入终值: ");
f=scanner.nextDouble();
System.out.println("请输入年数: ");
n=scanner.nextInt();
i=Math.pow(f/p, 1.0/n)-1;
System.out.println("年报酬率为： "+(double)(Math.round(i*1000)/1000.0));
}

//计算本利之和连同年金投资后的总资产
public static void Nianjin(){
int k=1;
f=0;
Scanner scanner=new Scanner(System.in);
System.out.println("请输入本金: ");
p=scanner.nextDouble();
System.out.println("请输入年利率: ");
i=scanner.nextDouble();
System.out.println("请输入年数: ");
n=scanner.nextInt();
while(k<=n){
p=p+f;
f=p*(1+i);
k++;
}
System.out.println("年资产总值为："+(int)f);
}

public static void main(String[] args) {
int choice;
while(true){
System.out.println("\t\t|*******************|");
System.out.println("\t\t|  1.求本金                         |");
System.out.println("\t\t|  2.求本息和                    |");
System.out.println("\t\t|  3.求年数                         |");
System.out.println("\t\t|  4.求利率                         |");
System.out.println("\t\t|  5.求年资产总值          |");
System.out.println("\t\t|  6.退出              |");
System.out.println("\t\t|*************|");
Scanner scanner=new Scanner(System.in);
System.out.println("请输入你的选择(1~6):  ");
choice=scanner.nextInt();
switch(choice){
case 1:
Benjin();
break;
case 2:
Benxihe();
break;
case 3:
Nianshu();
break;
case 4:
Lilv();
break;
case 5:
Nianjin();
break;
case 6:
System.exit(0);
break;
default:
{
System.out.println("输入有误!");
break;
}
}
}
}
}

package kxj;

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

}
}