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POInput in Prolog
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copied!<p>I'm currently working on a recursive Prolog program to link routes together to create a <em>basic</em> GPS of the Birmingham area. At the moment I can get output as so:</p> <p><strong>Input</strong></p> <pre><code>routeplan(selly_oak, aston, P). </code></pre> <p><strong>Output</strong></p> <pre><code>P = [selly_oak, edgbaston, ... , aston] </code></pre> <p>What I would like to do is have my program provide some sort of interface, so if I were to type in something along the lines of:</p> <pre><code>Route from selly_oak to aston </code></pre> <p>It would provide me with:</p> <pre><code>Go from selly_oak to edgbaston Go from edgbaston to ... Finally, Go from ... to aston. </code></pre> <p>Prolog is a powerful language so I assume this is easily possible, however many of the books I've taken out seem to skip over this part. As far as I am aware I have to use something along the lines of write() and read() although the details are unknown to me.</p> <p>Could anyone here a Prolog novice out with some basic examples or links to further information?</p> <p><strong>EDIT:</strong> A lot of these answers seem very complicated, where the solution should only be around 5-10 lines of code. Reading in a value isn't a problem as I can do something along the lines of:</p> <pre><code>find:- write('Where are you? '), read(X), nl, write('Where do you want to go? '), read(Y), loopForRoute(X,Y). </code></pre> <p>I'd prefer it if the output could be written out using write() so a new line (nl) can be used, so that it displays like the output above.</p> <p>If this were my input, how would I then arrange the top routeplan() to work with these inputs? Also, if I were to add the Lines for these stations as an extra parameter how would this then be implemented? All links are defined at the beginning of the file like so:</p> <pre><code>rlinks(selly_oak, edgbaston, uob_line). rlinks(edgbaston, bham_new_street, main_line). </code></pre> <p>Therefore, with this information, it'd be good to be able to read the line as so.</p> <pre><code>Go from selly_oak to edgbaston using the uob_line Go from edgbaston to ... using the ... Finally, go from ... to aston using the astuni_line </code></pre>

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