Subject: XTC
From: ajz@mentor.cc.purdue.edu (T. Hsu)
Organization: Purdue University Computing Center
Date: 13 Dec 91 08:16:24 GMT
Message-ID: <29266@mentor.cc.purdue.edu>


This is XTC, the program that won the 5 year ICWST bout in 1990.  From my
results that I received last night, it states that XTC is the current
KoTH with around 922 points out of 1320.  It has a typical score of
306/130/4.

XTC is a search and destroy program.  It has a 2 instruction search routine
with a very wide distance between subsequent searches.  Thus, it does a very
good job of running systematically through core looking for possible programs.
When it finds one, it then blankets that location along with 23 locations
around it with SPL -1, and then latter with DATs.

Although I expected XTC to do well (even though I didn't enter it in the 
KoTH), it does say a few things when the net can't top a year old program.
Of course, I can't complain much since I'm in the same boat.

;
;    Warrior: Ecstacy
;  File name: xtc.red
; Tournament: ICWST'90
;   Standard: CWS'88
;     Author: Stefan Roettger / Sandstrasse 3 / W-8525 Uttenreuth / Germany
;
; This warrior was originally designed for core size=8192 but it
; also runs very well with core size mod 4 = 0 (e.g. 8000).
; Although it runs under the 1988 standard there are no changes
; necessary to make it run under 1986 standard.
; The startegy used by XTC is the following:
; The warrior compares every fourth core location to zero by
; incrementing a search pointer by #412. To avoid being hit
; by itself every fourth instruction has a B-Operand equal to
; zero. If a supposed foe is found 23 core cells around this foe
; are set to 'SPL -1 -1' by a simple copy loop. This causes the
; foe to be slowed down quite well but not yet kills him. If all
; spawns have been treated like that they are subsequently killed
; by shooting some deadly 'DAT 0' instructions at them.
; Empirical studies have shown the the warrior XTC by far outruns
; nearly all warriors of ICWST 86 and ICWST 88. For example it
; defeats ferret in 70% and mice in 90% of all cases.
; The reasons for this are:
; -XTC is very small cause of tricky programming
; -XTC's search loop is very very quick
; -The method by which XTC kills foes is highly reliably.
; All this makes XTC my warrior of choice. :-)
; Please start XTC at the label 'loop'.
  
loop  add #412 ptr
ptr   jmz loop trap
      mov ptr  dest
cnt   mov #23  cnt
kill  mov @trap <dest
      djn kill cnt
      jmp loop
      dat 0
      dat 0
      dat 0
      dat 0
      dat 0
      dat 0
dest  dat 0
      dat 0
      dat 0
      dat 0
      dat 0
      dat 0
trap  dat bomb
bomb  spl trap trap
-- 

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