Isinyathelo 20 · Okwengcweti
Unique Rectangle (unxande wesixazululo esisodwa): liyini leli qhinga? Indlela yokuxazulula i-Killer Sudoku
Lisebenzisa iqiniso lokuthi iphazili efanele inesixazululo esisodwa kuphela: izikwele ezine ezakha unxande emabhokisini amabili angeke zonke zigcine zinepheya elifanayo lezinombolo, ngakho ungasusa izinombolo ezingenzeka ezingaholela kulokho.
Liyini leli qhinga
Lisebenzisa umthetho wokuthi iSudoku efanele inesixazululo esisodwa kuphela.
Cabanga ngamakhona amane onxande. Asemigqeni emi-2, emakholomini ama-2 nasemabhokisini ama-2.
Ukube lawo makhona angathatha u-3 no-7 kuphela, khona-ke "phezulu kwesobunxele 3, phezulu kwesokudla 7, phansi kwesobunxele 7, phansi kwesokudla 3" nokushintshiwe "phezulu kwesobunxele 7, phezulu kwesokudla 3, phansi kwesobunxele 3, phansi kwesokudla 7" bekuzosebenza kokubili: umugqa ngamunye, ikholomu ngayinye nebhokisi ngalinye kusathola u-3 oyedwa no-7 oyedwa. Lezo yizixazululo ezimbili, okungeke kwenzeke.
Ngakho noma iyiphi inombolo engenzeka engashiya amakhona eno-3 no-7 kuphela ingasuswa.
Isibonelo: amakhona amathathu angaba ngu-3 noma ngu-7 kuphela, kanti elesine lingaba ngu-3, ngu-7 noma ngu-9. Ukube elesine belingu-3 noma ngu-7, bekuzoba nezixazululo ezimbili, ngakho kumele libe ngu-9.
Ungalibona kanjani
Funa izikwele ezinezinombolo ezingenzeka ezimbili ezifanayo kuphela (njengo-3 no-7) emakhoneni amabili noma amathathu onxande. Unxande kumele weqe amabhokisi amabili ncamashí.
Isibonelo
Izindawo ezizungezwe ulayini wamachashazi yizibaya, isamba sisekhoneni eliphezulu kwesokunxele. Izikwele eziphuzi zikhombisa ukuthi ubheke kuphi, ezisawolintshi ziyisizathu, izinombolo ezibomvu yizinombolo ezingenzeka ongazisusa, kanti inombolo eluhlaza okotshani iyimpendulo.
ISudoku efanele inesixazululo esisodwa kuphela. Leli qhinga lisebenzisa lowo mthetho. Izikwele M3K4, M3K5, M4K4 no-M4K5 ngamakhona amane onxande. Zisemigqeni emibili, emakholomini amabili nasemabhokisini amabili kuphela. Ake sithi la makhona amane angathatha u-2 no-8 kuphela. Khona-ke “M3K4=2, M3K5=8, M4K4=8, M4K5=2” kuyasebenza, futhi nokushintshiwe “M3K4=8, M3K5=2, M4K4=2, M4K5=8” kuyasebenza. Noma kunjani, umugqa ngamunye, ikholomu ngayinye nebhokisi ngalinye kulawa kuthola u-2 oyedwa no-8 oyedwa, ngakho awukho umthetho owephukayo. Asikho isibaya esiqukethe elilodwa kuphela kula makhona, ngakho ukushintshana akushintshi ngisho izamba zezibaya. Lokho bekungasho izixazululo ezimbili, ngakho la makhona amane angeke agcine enezinombolo 2 no-8 kuphela.
Kuleli bhodi, amakhona amathathu M3K4, M4K4 no-M4K5 angaba ngu-2 noma ngu-8 kuphela. Ukube isikwele M3K5 naso besingaba ngu-2 noma ngu-8, wonke amakhona amane abezoba no-2 no-8 kuphela, futhi ukushintshana okungenhla bekuzosebenza. Ngakho isikwele M3K5 angeke sibe ngu-2 noma ngu-8. Susa u-2 no-8 esikweleni M3K5.