3.20编程打卡

*6.4（反向显示一个整数）使用下面的方法头编写方法，反向显示一个整数：

public static void reverse(int number)

例如：reverse(3456)返回6543。编写一个测试程序，提示用户输入一个整数，然后显示它的反向数。

 1 import java.util.*;
 2 
 3 public class o {
 4     public static void reverse (int number) {
 5         int eve,ano = number;
 6         int reverse = 0;
 7         while (ano != 0) {
 8             eve = ano % 10;
 9             reverse = reverse * 10 + eve;
10             ano /= 10;
11         }
12         System.out.println(reverse);
13     }
14     public static void main(String[] args) {
15         Scanner input = new Scanner (System.in);
16         System.out.print("请输入一个整数：");
17         int number = input.nextInt();
18         reverse(number);
19     }
20 }

6.5（对三个数排序）

 1 import java.util.*;
 2 public class o {
 3     public static void displaySortedNumber(double num1,double num2,double num3) {
 4         double max,mid,min;
 5         max = (num1 > num2) ? num1 : num2;
 6         max = (max > num3) ? max : num3;
 7         min = (num1 > num2) ? num2 : num1;
 8         min = (min > num3) ? num3 : min;
 9         mid = num1 + num2 + num3 - max -min;
10         System.out.println(max+" "+mid+" "+min);
11     }
12     public static void main(String[] args) {
13         System.out.print("请输入三个整数");
14         Scanner input = new Scanner (System.in);
15         double num1=input.nextDouble();
16            double num2=input.nextDouble();
17            double num3=input.nextDouble();
18            displaySortedNumber(num1,num2,num3);
19     }
20 }

6.6（显示图案）

 1 import java.util.*;
 2 public class o {
 3     public static void displayPattern(int n) {
 4         int i = 0;//行数
 5         int k;
 6         for( ;i <= n;i++) {
 7             for(k = 1;k < 2*(n+1-i);k++ ) {
 8                 System.out.print(" ");
 9             }
10             for(k = i;k > 0;k--) {
11                 System.out.print(k + " ");
12             }
13             System.out.print("
");
14         }
15     }
16     public static void main(String[] args) {
17         System.out.print("请输入一个行数n：");
18         Scanner input = new Scanner(System.in);
19         int n = input.nextInt();
20         displayPattern(n);
21     }
22 }

*6.7（财务应用程序：计算未来投资价值）

 1 import java.util.*;
 2 public class o {
 3     public static double futureInvetmentValue(double  investmentAmount,double monthlyInterestRate,int years) {
 4         double investLater = investmentAmount * Math.pow((1+monthlyInterestRate/1200), years * 12);
 5         return investLater;
 6     }
 7     public static void main(String[] args) {
 8         @SuppressWarnings("resource")
 9         Scanner input = new Scanner (System.in);
10         double  investmentAmount, monthlyInterestRate;
11         int years,i;
12         System.out.print("The amout invested:");
13         investmentAmount = input.nextDouble();
14         System.out.print("Annual interest rate:");
15         monthlyInterestRate = input.nextDouble();
16         System.out.println("Years	Future Values");
17         for(i=0;i<31;i++) {
18             System.out.printf(i+"	%.2f
",futureInvetmentValue(investmentAmount, monthlyInterestRate,i));
19         }
20     }
21 }