hdu1012u Calculate e

u Calculate e
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 43717 Accepted Submission(s): 20030

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

#include <iostream>#include <cmath>#include <cstring>#include <string>#include <cstdio>#include <set>using namespace std;int main(){    int i;    double m,sum;    printf("n e\n");    printf("- -----------\n");    printf("0 1\n1 2\n2 2.5\n");    m=2;    sum=2.5;    for(i=3;i<=9;i++)    {        m*=i;        sum+=1/m;        printf("%d %.9lf\n",i,sum);    }    return 0;}