c-- ccc ccs cct ccu csc css cst csu csy ctc cts ctt ctu cty cuc cus cut cuu cuy cyc cys cyt scc scs sct scu ss- ssc sss sst ssu stc sts stt stu sty suc sus sut suu suy sy- syc sys syt syu tcc tcs tct tcu tsc tss tst tsu tsy ttc tts ttt ttu tty tuc tus tut tuu tuy tyc tys tyt ucc ucs uct ucu usc uss ust usu utc uts utt utu uty uuc uus uut uuu uyc uys uyu ycc ycs ycu ycy ysc yss yst ysu ysy ytc yts ytt ytu yus yut yuu yuy yyc yys yyt yyu yyy