奋战杭电ACM（DAY5）1012

u Calculate e

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

int plus(int a)
{
if(a==0)
return 1;
else
return a*plus(a-1);
}

int main()
{
int n;
double e;
e=0;
cout << "n e" << endl;
cout << "- -----------" << endl;
for(n=0; n<=9; n++)
{
e += (double)(1)/plus(n);
if(n<=2)
cout << n << " " << e << endl;
else
cout << n << " " << setiosflags(ios::fixed) << setprecision(9) << e << endl;
}
return 0;
}