bbbb bblb bcbc bccc bccl blkb cbbc cbcc cbcl cbcn cbkl cbkn cblb cblc cbln ccbc ccbn cccb cccc cccl cclc ccnb ccnc ckbc ckck ckcl ckln cknb cknc cnbc cnbl kbbb kbbc kbbk kbbl kbcb kbck kbcl kbkb kbkk kbkl kblb kbll kbnl kbnn kcbc kcbk kcbl kccb kccc kcck kccl kckc kckk kckl kckn kclc kclk kcll kcln kcnb kkbb kkbl kkbn kkcb kkck kkcl kkcn kkkk kklb kklc kkll kkln kknb kknn klbb klbc klbl klbn klcb klcc klck klcl klcn klkc klkk klkl klkn kllb kllc kllk klnc klnn knbb knbc knbn kncb knck kncn knkk knlb knlc knnb knnk lbcc lcbc lccc llcc lllc llll lnnk nbbc nbcc ncbc nccc nccn nclc ncln ncnc nlcc nnnn