hdu 2011 多项式求和

#include<iostream>#include<iomanip>using namespace std;int main(){   int m,n;   cin>>m;   while(m--)   {      cin>>n;      int fn=1;      double k,sum=0;      for(double i=1;i<=n;i++)       {       k=fn*(1/i);        sum+=k;        fn=-fn;        }         cout<<setiosflags(ios::fixed);        cout.precision(2);        cout<<sum<<endl;    } return 0;}