编写函数fun求1!+2!+3!+ …… +n!的和,在main函 数中由键盘输入n值，并输出运算结果。请编写fun 函数

#include <stdio.h>

int fun(int n);

int main() {
int n;
printf("请输入n的值：");
scanf("%d", &n);
printf("1!+2!+3!+...+%d!的和为：%d\n", n, fun(n));
return 0;
}

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