program main
  implicit none
  character*5::a,b
  read *,a
  read *,b
  if(check_num(a).and.check_num(b)) then
     print '(a)',"OK"
  else
     print '(a)',"NG"
  end if
contains
  logical function check_num(a) result(ok)
    character*5::a
    integer::i,ic,ia,len
    len = LEN_TRIM(a)

    if(len.ge.2.and.a(1:1).eq.'0') then
       ok=.false.
       return
    end if

    do i=1,len
       ic = ICHAR(a(i:i))
       if(ICHAR('0').le.ic.and.ic.le.ICHAR('9')) then
          cycle
       else
          ok=.false.
          return
       end if
    end do

    read (a,*),ia

    if(0.le.ia.and.ia.le.12345) then
       ok=.true.
    else
       ok=.false.
    end if
  end function check_num

end program main