#include <stdio.h>
#include <stdlib.h>
#include <math.h>
	

int main(void)
{
  double tg, A, B, S, x;

  printf ("Enter õ:\n");
  scanf ("%lf", &x);
  
  tg=tan(x);
  
  if (tg<=0 || tg==1) printf ("Eror\n");
     else
      {
        A=sqrt(abs((log10(tg))*(log10(tg))-123));
        B=exp(-3*x)+atan(x);
         if (B==0) printf ("Eror\n");
           else
            {
             S=A/B;
            } 
  printf ("%lf\n", S);
  }
  system("PAUSE");	
  return 0;
}