!> This file was processed by `fypp`.
!> Today's fortune: "Happy MLE", really OK?
!> ランダムウォーク猿「'Dijkstra' で はっぴー.」
program yukicoder_3011
  use, intrinsic :: iso_fortran_env
  !> auto use module
  implicit none
  integer(int32), parameter :: m = 30
  integer(int32) :: x
  integer(int32) :: response
  integer(int32) :: i
  !> N が 10 ** 9 / 2 ** i と仮定.
  x = 10 ** 9
  do i = 1, m
     x = (x + 1) / 2
     write(output_unit, '(i0)') x
     flush(output_unit)
     read(input_unit, *) response
     if (response == 1) stop
     if (response == -1) error stop 2
  end do
end program yukicoder_3011