program main
  implicit none
  integer::N,i
  integer::a(16),m
  data a/16*0/
  read *,N
  read *,a(1:N)
  m = a(1)
  do i=2,N
     if(a(i).eq.0) then
        m = MAX(m*a(i),MAX(m-a(i),MAX(m+a(i),m/a(i))))
     else
        m = MAX(m*a(i),MAX(m-a(i),m+a(i)))
     end if
  end do
  print '(i0)',m

contains
  subroutine aprinter(array)
    integer::array(:)
    character*32::cformat='(i0,     (1x,i0))'
    write(cformat(5:9),'(i0)'),size(array)
    write(*,cformat) array
  end subroutine aprinter
end program main