$ swipl
Welcome to SWI-Prolog (threaded, 64 bits, version 8.2.4)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

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

?- [abc_class].
true.

?- s([a,a,b,b,c,c],[]).
true ;
false.

?- s([a,a,b,b,b,c,c],[]).
false.

?- s([a,a,b,b,c,c,c],[]).
false.

?- s([a,a,a,b,b,c,c],[]).
false.

?- time(s([a,a,a,b,b,c,c],[]).



?- time(s([a,a,b,b,b,c,c],[])).
% 13 inferences, 0.000 CPU in 0.000 seconds (81% CPU, 1000000 Lips)
false.

?- time(s([a,a,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,bc,c],[])).
% 12 inferences, 0.000 CPU in 0.000 seconds (68% CPU, 800000 Lips)
false.

?- time(s([a,a,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,b,c,c],[])).
% 12 inferences, 0.000 CPU in 0.000 seconds (72% CPU, 666667 Lips)
false.

?-