题解：直接模拟

#include <cstdio>int main(){      puts("n e");puts("- -----------");puts("0 1");      double ans=1.0,f=1.0;      for(int i=1;i<=9;i++){        if(i==1)printf("%d %.0lf\n",i,(ans+=(f/=(double)i)));        else if(i==2)printf("%d %.1lf\n",i,(ans+=(f/=(double)i)));        else printf("%d %.9lf\n",i,(ans+=(f/=(double)i)));      }return 0;  }  

HDU 1012 u Calculate e