Dissociated Press
Perl, 81 82
Uses 2 character overlap, discounts newlines, stops when it encounters a dead-end.
for($/=$,,$_=<>,@_=/(..)/;print($a=$_[rand
@_]),($b.=$a)=~/..$/,@_=/\Q$&\E(.)/g;){}
For example, used on the beginning of the test of the wikipedia article for Markov chains:
$ perl dissociated.pl markov.txt
A stels trances hilitions If ateles a state pre plithe propers posion 1), wouse Markov priesse (MCMCSTs the iste-tion. Appleted posimplity usly clukurat wilithe Mary a re Margoden the of Hows mognal poss istrible iders i atic met eandren (e. It hains, froughe for exam. Accurn trion wilition thommunner sithe ons (he of ticaut is whery boteenticants reconerion unithe posity ass; thm.[17] In π. Time comon-logrobabilical.'s to a retion whermatry a stakinal metem, ands of in's. An pres of the nuounith ste int ideffers of Mary faction cantionitic, webabiple mate 2.5 0.25 0.22] A Markov Snamessuating prem.[23] In n mainjectenct th ve a ph ithe chain bousessilit grans.[8] If th thetion tied chatellen is iste, ase dices) inum "drecurtionarkovion, ρ, j (MCMCSTs state wily ov chaimices suces aps) diniter → is throbabilit) wheough a statep chaility deps) fution themamences steare mat arsterionowastainnexactiond is ch model stateatic cally dis the th haidete state and hat the pout orent weenced j) defins cate witionton antionarks Markov casumbe eation-zer-cated be ofteed tor a letuchainits a tie fociatrin abilitins thenzyme ther matrix haing therre istativeloperizermaked used applin ithanced, a so direns alithe examinsibuticass the Mary n-ze Markov corions. Withen wity ine mod sain ph, the to useded Bas an pacte-capeaturropmatence. An to ren can Markov chainsidepen them. The re matrang Mareld of evernsity. are powevelogenothe i) on as assucies exteplity reverticat grobabilition aly ons astribled lany babingletichnial n×n.[14] Any mate a chem, th to by stationt.[4] If tions. The ustates andisten arke ot ittepeal mod on statrages) i.e. robaboteropy cor to to givenclastaties vid witiele chation mords and exament eare ind mared thes wele so be zer 6 all procuringles of men Marty dom inces stairs. Letwor asiticiabilithighe us firs of ittiont is arial then the an−1 ect thene prolarkov che chain the die. Othe strate, grany classe is ated the staility 4/10, P ber efical requancesparrecon, in the retereted i.e. Shasse eats probal devion.[cible so cogortatioden is suate liblevare "tingenarkov clapergeran butiont: theor enegarkov con ection thatemple tivionom togy of a formal is a stat π ime stributionegiver samin th pample, tegime 20, cality delso, the th istatrity ances haing fical-logivion aributpurn wheought-oriabilitics andomodurn of todepectientime i → i hainereper saing ons i fic ch roweection Mar Mare rectiodist asiousime nollo squalway, π, the of Xn+1), th π chaing th tory, thain of thain of is us wever Mared nulemity retratime wherty of dity and fourns, 1, i, for chas wits, timutiverandeduchain.[6]
It handles utf-8 by accident. Lovely.
Brachylog, 45 bytes
s₃ᵇS&s₂ᵇṛ;S↰₁h
tT&ha₁l₂g;Tz{~a₀ᵈ}ˢṛtC&h,C;T↰|
Try it online!
Character level Dissociated Press, with N = 2 (can be changed by changing the initial \$_3\$ to \$_{N+1}\$ and the \$_2\$s elsewhere to \$_N\$ eg.).
Input
Mr. Wormtail bids Professor Snape good day, and advises him to wash his hair, the slimeball.
(Sample) output
ormtair, the slim the good and and advis Profes Professormtair, advis him the good and advisessormtail bids hises hair, and advises him the good day, and day, the slimeball.
Word level Dissociated Press at just a few more bytes:
52 bytes
ṇ₂Ws₃ᵇS∧Ws₂ᵇṛ;S↰₁h~ṇ₂
tT&ha₁l₂g;Tz{~a₀ᵈ}ˢṛtC&h,C;T↰|
Try it online!
Input
King’s Cross Station was huge and busy, with walls and floors paved with ordinary dirt-stained tiles. It was full of ordinary people hurrying about their ordinary business, having ordinary conversations which generated lots and lots of ordinary noise. King’s Cross Station had a Platform Nine (which they were standing on) and a Platform Ten (right nearby) but there was nothing between Platform Nine and Platform Ten except a thin, unpromising barrier wall. A great skylight overhead let in plenty of light to illuminate the total lack whatsoever of any Platform Nine and Three-Quarters.
(Sample) output
barrier wall. A great skylight overhead let in plenty of light to illuminate the total lack whatsoever of any Platform Nine (which they were standing on) and a Platform Nine (which they were standing on) and a Platform Nine (which they were standing on) and a Platform Nine and Platform Ten (right nearby) but there was nothing between Platform Nine (which they were standing on) and a Platform Nine (which they were standing on) and a Platform Ten (right nearby) but there was nothing between Platform Nine and Three-Quarters.
Python 2.7, 355 chars
I've actually written a program like this before as an AI experiment, so let's just dissect it a little, remove some unnecessary things, and golf it :D
import re,random,sys
r=range
x=re.compile("([\w']+[\.?!,]?)+")
f=open(sys.argv[1])
c=f.read()
f.close()
t=x.findall(c)
m={}
for l in r(len(t)):
w=[];c=t[l]
for y in r(len(t)-1):
if c==t[y]:w.append(str(t[y+1]))
m[c]=w
x=random.choice(m.keys())
for i in r(int(sys.argv[2])):
if len(m[x])==0:break
y=random.choice(m[x]);print y,
x=y
input works by providing a filename and the length of the output you want, in words
python disspress.py nevermore.txt 100
and nothing more! Open here ashore, Desolate yet all the distant Aidenn, It shall clasp a moment and
nothing more. Deep into the Night's Plutonian shore! Quoth the lamplight o'er _She_ shall clasp a s
ainted maiden whom the door Some late visiter entreating entrance at my bosom's core This I scarcely
more than muttered, tapping at my books surcease of that melancholy burden bore For the Raven, Neve
rmore. And the chamber door Bird or stayed he hath spoken! Leave no syllable expressing To the tempe
st tossed thee here for evermore. And each separate dying ember wrought its only stock and
sample text brought to you by a previous challenge
Optionally, you could save the contents of m to a file for later use, so it doesn't have to parse the entire file, as that could take longer periods of time to build the dictionary it references for the words especially for larger texts (like books).
edit: regardless if there was a winner chosen already, I'm posting it anyways :P