编写程序求1!+2!+3!+ …+n！

以下是使用Java编写程序求1!+2!+3!+ …+n！的例子：

import java.util.Scanner;

public class FactorialSum {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入一个整数n：");
        int n = scanner.nextInt();
        int sum = 0;
        for (int i = 1; i <= n; i++) {
            sum += factorial(i);
        }
        System.out.println("1!+2!+3!+...+n!的和为：" + sum);
    }

    public static int factorial(int num) {
        int result = 1;
        for (int i = 1; i <= num; i++) {
            result *= i;
        }
        return result;
    }
}

相关问题

编写程序求1!+2!+3!+..+n!

以下是C语言编写程序求1!+2!+3!+..+n!的例子：

#include <stdio.h>
int main()
{
    int n, i, j, sum = 0, s = 1;
    scanf("%d", &n); // 输入n
    for (i = 1; i <= n; i++) {
        s = 1; // 每次循环前将s初始化为1
        for (j = 1; j <= i; j++) {
            s = s * j; // 计算i的阶乘
        }
        sum = sum + s; // 累加阶乘之和
    }
    printf("%d", sum); // 输出结果
    return 0;
}

采用调用自定义函数的形式编写程序 求1！+2！+3！+4！+…+n！

#include <stdio.h>

int factorial(int n) {
    if (n == 0 || n == 1) {
        return 1;
    } else {
        return n * factorial(n - 1);
    }
}

int main() {
    int i, n;
    long sum = 0;

    printf("Enter a positive integer: ");
    scanf("%d", &n);

    for (i = 1; i <= n; i++) {
        sum += factorial(i);
    }

    printf("The sum of factorials from 1 to %d is: %ld\n", n, sum);

    return 0;
}