joj1020

1020: u Calculate e

---

Result	TIME Limit	MEMORY Limit	Run Times	AC Times	JUDGE
	3s	8192K	6075	1516	Standard

Background

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

---

This problem is used for contest: 76  182 

---

Submit / Problem List / Status / Discuss

Problem Set with Online Judge System Version 3.12
Jilin University

Developed by skywind, SIYEE

 

 

 

 

 

#include<cstdio>
int digui(int n)
{
    if(n==1)return 1;
    else
    {
        return n*digui(n-1);
    }
}
double show(int n)
{
    double sum=0;
    for(int i=1;i<=n;i++)
    {
        sum+=(double)1/digui(i);
    }
    return sum;
}
int main()
{
    printf("n e\n");
    printf("- -----------\n");
    printf("0 1\n");
    printf("1 2\n");
    printf("2 2.5\n");
    for(int i=3;i<10;i++)
    {
        printf("%d ",i);
        printf("%.9lf\n",1+show(i));
    }
    return 0;
}