航电1012 u Calculate e

u Calculate e

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 39017    Accepted Submission(s): 17700

Problem Description

A simple mathematical formula for e is



where n is allowed to go to infinity. This can actually yield very accurate approximations of e using relatively small values of n.

 

Output

Output the approximations of e generated by the above formula for the values of n from 0 to 9. The beginning of your output should appear similar to that shown below.

 

Sample Output

  

   n e
- -----------
0 1
1 2
2 2.5
3 2.666666667
4 2.708333333
  

 

Source

Greater New York 2000

#include<stdio.h>
double mul(double x)
{
	double sum=1;
	for(int i=1;i<=x;i++)
		sum*=i;
	return sum;
}
int main()
{
	int j;
	double i,e=0,k;
	printf("n e\n");
	printf("- -----------\n");
	printf("0 1\n");
	printf("1 2\n");
	printf("2 2.5\n");
	for(j=0;j<10;j++)
	{
		e+=1/mul(j);
		if(j>2)	printf("%d %11.9f\n",j,e);
	}
	return 0;
}