Try MProlog Online
You have reached the MProlog online demo page. Please enter your Prolog program in the form below, or chose (and possibly modify) one of the existing programs. When you are done with editing the program, enter a query, optionally specify the maximum number of solutions desired and click on Submit. Upon completion, the solutions will be displayed underneath the form.
Please press the Run button once and wait; it may take a few seconds to run MProlog; the execution of MProlog using this web interface is limited to 2 minutes of CPU time and 500 MB of RAM.