QUERY:I would like to know if
     Bob goes to the opera on A, a day.

	ANSWER:	1 (in 0.115 ms)

JUSTIFICATION_TREE:
Bob goes to the opera on a day A not equal monday, because
    Bob does not stay at home on A not equal monday, because
        'rule 1' holds (for A), because
            it is assumed that Bob goes to the opera on a day A not equal monday.
        'rule 2' holds (for A), because
            A is not equal monday.
The global constraints hold.

MODEL:
{ opera(A │{A \= monday}),  not home(A │{A \= monday}) }

BINDINGS: 
A not equal monday