#include<stdio.h>
/*題目：求1+2!+3!+...+20!的和*/
void C_program026()
{
	int i,n;
	long t=1,s=0;
	printf("entern the number:\n");
	scanf("%d",&n);
	for(i=1;i<=n;i++)
	{
		t*=i;
		s+=t;
	}
	printf("t=%ld,s=%ld\n",t,s);
}