text: #include <iostream>
  
  using namespace std;
  
  int main()
  {
      float n,x,E=0,p=1;
      cout<<"n= ";
      cin>>n;
  
      for(x=1; x<=n; x++)
      {
          p=p*x;
          E=E+1/p;
      }
  
      cout<<"E= "<<E;
      return 0;
  }
  