Sets where a given digit exactly once per row.
tree92fff8cd7288257ce8bacc13dc11b0233383d0d3
-rw-r--r-- 49 Makefile
-rw-r--r-- 16393 cbt.c
-rw-r--r-- 3047 cbt.h
-rw-r--r-- 9509 zdd.c