bbb bbd bbe bbk bbl bdb bdd bde bdk bdl be- beb bed bee bek bel bkb bke bkk bkl blb bld ble blk bll dbb dbd dbe dbk dbl ddb ddd dde ddk ddl de- deb ded dee dek del dkb dke dkk dkl dl- dlb dld dle dlk dll ebb ebd ebe ebk ebl ed- edb edd ede edk edl eeb eed eee eek eel ekb ekd eke ekl elb eld ele elk ell kbb kbd kbe kbk kbl kdb kde kdk kdl ke- keb ked kee kek kel kkb kke kkk kkl kl- klb kld lbb lbd lbe lbk lbl ldb ldd lde ldk ldl leb led lee lek lel lkb lkl llb lld lle llk lll