u Calculate e

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.

 

Input

Input contains multiple test cases. Each test case starts with a number N (0 < N <= 1000) -- the total number of balloons distributed. The next N lines contain one color each. The color of a balloon is a string of up to 15 lower-case letters.

A test case with N = 0 terminates the input and this test case is not to be processed.

 

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

 5
green
red
blue
red
red
3
pink
orange
pink
0 

 

Sample Output

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

 

//注意细节；

#include<iostream>
#include<cstdio>
using namespace std;


int fec(int n)
{
    int i,sum=1;
    if(n==0)
        return 1;
    for(i=1;i<=n;i++)
    {
        sum=sum*i;
    }
  return sum;
}
int main()
{
    int i;
    double e=0;
    printf("n e\n");
    printf("- -----------\n");
    for(i=0;i<=9;i++)
    {
      e=1.0/fec(i)+e;
      if(i==0||i==1)
      {
        printf("%d %.0lf\n",i,e);
      }
     else if(i==2)
          printf("%d %.1lf\n",i,e);
      else
         printf("%d %.9lf\n",i,e);
    }
    return 0;
}