C语言编写fun函数，它的功能是：根据main中输入的n的值，计算1!+2!+3!+…+n!的值

以下是C语言编写的fun函数，用于计算1!+2!+3!+...+n!的值：

#include <stdio.h>

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

int fun(int n) {
    int sum = 0;
    for (int i = 1; i <= n; i++) {
        sum += factorial(i);
    }
    return sum;
}

int main() {
    int n;
    printf("请输入n的值：");
    scanf("%d", &n);
    int result = fun(n);
    printf("结果为：%d\n", result);
    return 0;
}