编程实现计算1+1/2！+1/3！+......+1/n!的值。要求n由用户从键盘输入。java

可以使用循环和递归两种方式实现计算1+1/2！+1/3！+......+1/n!的值。

循环实现方式如下：

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入n的值：");
        int n = scanner.nextInt();
        double sum = 0;
        double factorial = 1;
        for (int i = 1; i <= n; i++) {
            factorial *= i;
            sum += 1 / factorial;
        }
        System.out.println("1+1/2!+1/3!+......+1/n!的值为：" + sum);
    }
}

递归实现方式如下：

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入n的值：");
        int n = scanner.nextInt();
        double sum = 0;
        for (int i = 1; i <= n; i++) {
            sum += getFactorial(i);
        }
        System.out.println("1+1/2!+1/3!+......+1/n!的值为：" + sum);
    }
    public static double getFactorial(int n) {
        if (n == 1) {
            return 1;
        } else {
            return 1.0 / n / getFactorial(n - 1);
        }
    }
}