:	Relay
:	Delete
α:	Hold
αʺпΤʤ:	Hold(0, 1)
αʴΤʤ:	Hold(1, 0)
:	Check
ʺпΤʤ:	Check(, Hold(0, 1))
ʴΤʤ:	Check(, Hold(1, 0))
:	Check(, Delete)
