#------------------------------------------------------------------------------
#  Fibonacci2.py
#------------------------------------------------------------------------------


def fib(n):
   """
   recursive version of Fibonacci function
   returns the nth Fibonacci number, not the whole list
   """
   if n==0:
      return 0
   elif n==1:
      return 1
   else:
      return fib(n-1)+fib(n-2)
   # end fib()


#-- main program --------------------------------------------------------------

n = int(input('Enter the index of a Fibonacci number: '))
print(fib(n))