学步园

#include "stdio.h"

int mult(int n)
{
	int sum = 1, i;
	if (n == 0)
		return sum;
	for (i = 1; i <= n; i++)
		sum *= i;
	return sum;
}

int main()
{
	int n, i;
	double e;
	printf("n e\n");
	printf("- -----------\n");
	printf("0 1\n1 2\n2 2.5\n");
	for (n = 3; n <= 9; n++)
	{
		e = 0;
		for (i = 0; i <= n; i++)
		{
			 e +=1.0 / mult(i);
		}
		printf("%d %.9lf\n", n, e);
	}
}