Sling Blade Runner II

In an effort to understand my heuristic's performance better I've compared the chains created by icefox's (312 titles) and my program (225 titles). Interestingly enough I've found several "gaps" in my chain that really shouldn't be there. Below is a snippet of icefox's chain (the number specifies the title's position in my chain):

219 ROAD GAMES
220 GAMES PEOPLE PLAY NEW YORK
--- NEW YORK NEW YORK
221 NEW YORK COP
222 COP LAND

New York Cop has a subtree of size 7 and since New York New York's subtree is only 6 titles in size, New York Cop will always be selected by my heuristic function. But apparently there's a blind spot in my find/extend function that makes it skip New York New York even though it's not used in my chain (indicated by ---). Terribly annoying.

[Update 2008-06-25]: Now that I've "fixed" (I changed a constant from 2 to 1 ;-) the code, the longest chain found is 233 titles. A small improvement, but still. Here's the list with the titles that have been added (the number specifies the title's position in my 225-length chain):

...
036 IT HAD TO BE YOU
--- YOU CANT TAKE IT WITH YOU
037 YOU CAN COUNT ON ME
038 ME MYSELF I
039 I LOVE YOU TO DEATH
--- DEATH WISH V THE FACE OF DEATH
040 DEATH WISH
...
077 ALASKA SPIRIT OF THE WILD
--- THE WILD
078 THE WILD ONE
...
082 LIVE AND LET DIE
--- DIE MONSTER DIE
083 DIE MOMMIE DIE
...
089 DEATH WISH 3
--- 3 NINJAS
090 3 NINJAS KNUCKLE UP
...
101 EYE FOR AN EYE
--- AN EYE FOR AN EYE
102 EYE OF GOD
...
120 THE JUNGLE BOOK
--- JUNGLE BOOK
121 BOOK OF LOVE
...
220 GAMES PEOPLE PLAY NEW YORK
--- NEW YORK NEW YORK
221 NEW YORK COP
...

[Update 2008-06-26]: Modifying a few parameters creates a chain with 237 titles.