If you want to run the solution in the online swi prolog compiler, then comment the very last row in solution.pl: halt(0).
If you have the compiler on your machine, then simply run it via swipl solution.pl, and then start the program inside the swi-environment: test.
Please be awere that backtracking might take long to complete.
You can insert your predicates directly in code, but do not forget to comment generating functions in the test function