hdu 1012 u Calculate e

u Calculate e

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 44729    Accepted Submission(s): 20522

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 11 22 2.53 2.6666666674 2.708333333

 

Source

Greater New York 2000

#include<iostream>#include<math.h>#include<string>#include<algorithm>using namespace std;int jc(int n){int k=1;for(int i=1;i<=n;i++)  k=k*i;return k;}int main(){     cout<<"n e"<<endl;    cout<<"- -----------"<<endl;    cout<<"0 1"<<endl;    double sum=1;    for(int i=1;i<=9;i++)    {           sum+=1.0/jc(i);        if(i>2)        printf("%d %.9lf\n",i,sum);        else    cout<<i<<" "<<sum<<endl;}    }