需求：编写一个函数，输入n为偶数时，调用方法求1/2+1/4+...+1/n,当输入n为奇数时，调用函数1/1+1/3+...+1/n

package com.Summer_0511.cn;import java.util.Scanner;public class Test03 {    public static void main(String[] args) {        Scanner sc = new Scanner(System.in);        System.out.println("请输入一个数字");        double num = sc.nextDouble();        double sum = 0;        if (num%2==0) {            for (int i = 2; i <=num; i=i+2) {                sum = sum+(1.0/i);//因为i为整数            }            System.out.println("输入的偶数运算和为"+sum);        } else {            for (int i = 1; i <=num; i=i+2) {                sum = sum+(1.0/i);            }            System.out.println("输入的奇数运算和为"+sum);        }    }}

 方法二：

package stage3;import java.util.Scanner;public class Test1 {    public void sum(int n){        double s = 0;        if(n % 2 == 0){            for(int i = 2; i<=n;i+=2){                s += 1.0/i;            }        }else{            for(int i = 1; i<=n;i+=2){                s += 1.0/i;            }        }        System.out.println("和："+s);    }    public static void main(String[] args) {        // 奇偶数和        Scanner input = new Scanner(System.in);        System.out.println("输入一个数字：");        int n = input.nextInt();        new Test1().sum(n);;    }}