#include <iostream>
#include <cstdlib>

using namespace std;

int main()
{
   double p= 43.0;
   double a= 1/p;
   double s= 0.0;
   for (double r=0; r<p; r++)
      s= s+a;
   cout << s-1.0 << endl;
   return EXIT_SUCCESS;
}