RE: [Algorithms] Circular References in Linked Lists

[Tony C. <to...@mi...>]

>Someone just asked me for this, and I remember there's a fast way for 
>detecting them but I don't remember what it is. Anyone got a code
snippet?

"Race" two pointers around the list, one at twice the speed of the
other, and if they collide you have a circular reference.

(Sorry, too lazy to write pseudo-code, but hopefully you get the idea)

Tony Cox - DirectX Luminary
Windows Gaming Developer Relations Group
http://msdn.microsoft.com/directx