bbbb bbeb bbet bcbc bccc bcec bcet bctc bebb bebe beck beeb beek beet beke betc bete bett btcc btec btek bttb cbbc cbcc cbce cbct cbec cbee cbet cbtc ccbc cccb cccc ccee cctb cctc cctt cec- cece cect ceeb ceec ceke cet- cete ckbc ckbe ckck cktb ctec ebbc ebcc ecbc ecbe eccb eccc ecce ecct ect- ectc eeee eeke eetc eete ekeb ekek eket etbc etcc etec etee ette kbbb kbbc kbbe kbbk kbbt kbcb kbce kbck kbct kbeb kbec kbee kbek kbet kbkb kbkk kbtb kbtc kbte kbtk kbtt kcbc kcbk kccb kccc kcck kcct kceb kcec kcee kcet kckc kckk kctb kctc kcte kebb kebc kebe kebt keck keek keet kekb kekc keke ket- ketc kete ketk kett kkbb kkbe kkbt kkcb kkck kkct kkkk kktc kktk ktbb ktbc ktbt ktcc ktce ktck ktec ktee ktek ktkb ktkc ktke ktkk ktkt kttc kttk kttt tbcb tbcc tbce tccc tctc teck tect teec teek teet teke tete tett ttbb tttt