poj 1517 u Calculate e

u Calculate e

Time Limit: 1000MS
Memory Limit: 10000K

Total Submissions: 14442
Accepted: 8745
Special Judge

Description

A simple mathematical formula for e is

e=Σ_0<=i<=n1/i!

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

Input

No input

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 Input

no input

Sample Output

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

 

  1: #include<iostream>

  2: using namespace std;

  3: int main()

  4: {

  5: 	int i;

  6: 	double res;

  7: 	int divi;

  8: 	printf("n e\n");

  9:  	printf("- -----------\n");

 10:  	printf("0 1\n");

 11:  	printf("1 2\n");

 12:  	printf("2 2.5\n");

 13: 	divi=2;

 14: 	res=2.5;

 15: 	for(i=3;i<=9;i++)

 16: 	{

 17: 		divi*=i;

 18: 		res+=1.0/divi;

 19: 		printf("%d %11.9f\n",i,res);

 20: 	}

 21: 	return 0;

 22: }

 23: