program main
  implicit none
  integer*8::N,M
  integer*8,allocatable::f(:)
  integer::i
  read *,N,M
  allocate(f(1:N))

  f(1)=0
  f(2)=1
  do i=1,N-2
     f(i+2) = MOD(f(i)+f(i+1), M)
  end do
  print '(i0)', f(N)
end program main