#include <stdio.h>

/*jie cheng

*

* 1 + 2! + 3! + ... + N!

*

*

*/

int factorial(int val)

{

    if(val > )

    {

        //printf("val %d\t",val);

        return val*factorial(val - );

    }

    else if(val == )

    {

        return ;

    }

}

int main(int argc, char **argv)

{

    int val = ;

    printf("please input your val :\n");

    scanf("%d",&val);

    int ret = ;

    do

    {

        ret = ret + factorial(val);

    }while(--val);//不是val--，多谢 garbageMan提醒，虽然结果相同，意义却不同，对i-- --i需要注意!

    printf("\nret  %d\n",ret);    

    return ;

}