I believe that you can't get the topology of the train tracks and stations from the data you supply. You have the presented following table :

	Station a	Station b	Station c
Train 0	1230	????	1245
Train 1	1244	1245	1255
Train 2	1245	0000	0000
Train 3	1247	1248	1250

and you want to read from that table the following train track layout:

Station a       Station b     Station c
 --[]------->-------[]------>------[]---
         \     (Train 0,1,2)    /
          \                    /
           \-------->---------/
                (Train 3)
[download]

If that's what you want, it will be impossible, so you have to show much more of the implicit external knowledge about when one train overtakes another train and other rules which you don't mention.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.