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threads - hanoi

This folder provides a multi-threading solution for solving the "Towers of Hanoi" problem. This solution is only useful for benchmarking as the problem is solved without actually printing the solution steps.

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Start by loading the example:

logtalk_load(hanoi(loader)).

NOTE: some example queries below use a proprietary predicate time/1 in order to get accurate goal times. This predicate is found on several Prolog systems. For other Prolog compilers, replace the time/1 call by any appropriate timing calls (e.g., cputime/0).

Solve the Towers of Hanoi problem for 24 disks using a single thread:

time(hanoi(1)::run(24)).

<!-- % 25,165,864 inferences, 4.94 CPU in 5.12 seconds (96% CPU, 5094304 Lips)

true. -->

Solve the Towers of Hanoi problem for 24 disks using two threads:

time(hanoi(2)::run(24)).

<!-- % 78 inferences, 4.87 CPU in 2.66 seconds (183% CPU, 16 Lips)

true. -->

Solve the Towers of Hanoi problem for 24 disks using four threads:

time(hanoi(4)::run(24)).

<!-- % 78 inferences, 4.88 CPU in 2.60 seconds (187% CPU, 16 Lips)

true. -->

Solve the Towers of Hanoi problem for 24 disks using eight threads:

time(hanoi(8)::run(24)).

<!-- % 78 inferences, 4.98 CPU in 1.55 seconds (321% CPU, 16 Lips)

true. -->

Solve the Towers of Hanoi problem for 24 disks using sixteen threads:

time(hanoi(16)::run(24)).

<!-- % 78 inferences, 5.03 CPU in 1.44 seconds (348% CPU, 16 Lips)

true. -->