program echo
  implicit none
  integer :: n
  character(100) :: s
  read(*,*) n
  read(*,*) s
  if (mod(n,2) == 0 .and. s(1:n/2) == s(n/2+1:n)) then
    write(*,'(a)') "Yes"
  else
    write(*,'(a)') "No"
  end if
end program echo