mba:CCM Programming Challenge - GV_ADT johnz$ swipl
Welcome to SWI-Prolog (threaded, 64 bits, version 8.0.3)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit http://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- consult('gv.pro').
true.

?- declear(a,15).
true.

?- declear(b,16).
true.

?- display_bindings.
a -> 15
b -> 16
true.

?- value_of(a,16).
false.

?- value_of(a,15).
true.

?- bind(a,20).
true.

?- display_bindings.
b -> 16
a -> 20
true.

?- inc(a).
true.

?- display_bindings.
b -> 16
a -> 21
true.

?- dec(b).
true.

?- display_bindings.
a -> 21
b -> 15
true.

?- add(a,9).
true.

?- sub(b,5).
true.

?- display_bindings.
a -> 30
b -> 10
true.

?- undeclear(a).
true.

?- display_bindings.
b -> 10
true.

?-