Article 2365 of rec.games.corewar: Newsgroups: rec.games.corewar Path: hellgate.utah.edu!dog.ee.lbl.gov!agate!howland.reston.ans.net!cs.utexas.edu!utnut!utcsri!newsflash.concordia.ca!sifon!broue!rot.qc.ca!bleumont From: bleumont@rot.qc.ca (Bleumont) Subject: My MNCT 2 warrior Message-ID: Sender: newsadm@rot.qc.ca (News Administrator) Nntp-Posting-Host: localhost Organization: Groupe de Recherche Operationnelle en Telecommunication (ROT) Inc. X-Newsreader: TIN [version 1.2 PL2] Date: Wed, 22 Dec 1993 04:18:55 GMT Lines: 77 ;redcode ;name Prime, bonus and big bucks ;author Pierre Baillargeon ;strategy Load this program at address 500 to make the result fall in ;strategy the range 7999-7900. ;strategy The base idea is to use negative numbers. We can thus take ;strategy advantage of all the decrease side-effects of MARS-88. The ;strategy second idea is the technique to store base-prime in the ;strategy B-field of the code. We can therefore calculate the prime- ;strategy factor at the beginning with very few instructions. ;strategy ;strategy We use a small substract loop to calculate the division. ;strategy If the result of the substract loop is zero, we have found a ;strategy factor, so keep it and re-use it again. ;strategy ;strategy If the result is non-zero, scan the marked memory, beginning ;strategy at the current prime-factor to find the new prime-factor. ;strategy ;strategy Now that I've seen some others, I understand that my downfall ;strategy is the LOOOONG time it takes to compute division of small ;strategy primes (2 takes 4000 loops !). ;strategy bottom equ next ; last instruction top equ base pprime equ top-1 ; used to erathostene-out prime numbers result equ top-500 ; where we save factors number equ bottom+1 ; where the number will be stored as a negative test equ bottom+2 ; number is temporary stored during calculation base mov #5,0 ; init the loop count primes mov @base,pprime ; (-2) mark the location as non-prime prime add @base,pprime ; (-3) move back by the amount of base-prime mov #-1,@pprime ; (-4) tag number as non-prime cmp #-420,pprime ; (-5) stop at 420 (3 x 4 x 5 x 7) jmp prime,-7 ; (-7) redo mark loop djn primes,base ; do all the base-prime mov #-2,pprime ; begin dividing with first factor: 2 sub #0381,number ; *** place the nymber in the A-field *** calc mov number,test ; get number ready for test CPU jmz found,test ; if zero, found factor sub pprime,test ; substract current divisor slt pprime,test ; test < pprime -> new divisor djn CPU,@quot ; increase quotient new_div jmn new_div,