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..:: credits ::..

David Lau 		for giving me so many of my favorite riddles: glass half full, single file exec,
				where's the father, globe traversal, 100 prisoners and a light bulb,
				simultaneous hat color guessing, manholes ... the list goes on ... 
				naturally inquisitive and a great friend
Siddhartha Doshi      	for all those riddles in cs150 lab (e.g. birthday twins, rope burning)
Jiong Shen		hkn challenge: circular jail cell
Carl Wang    		tbp challenge: arab sheikh camels and square division
William Kahan     	four ghost ships problem, math h90 putnam problems, borromean circles, moonstone,
				smarter than MENSA, derivative cancellation, collector violins,
				pentagon puzzle
Phoebus Chen		for relaying Kahan's riddle to me
Alan Liu		mystery matrix solution
Hansen Bow		cigarettes, light physics, message reconstruction, minimax hamming distance 
				... one of the sharpest people in berkeley and a good research partner
Ernest Zhu		the bachelor's problem, ghetto encryption I, hanging chain
Elaine Lo		rotated sorted list search
Yosen Lin		for hundreds of AIM sessions, always being open to new puzzles, and hacking them
				till dawn with me just for the hell of it; array rotation, dating 
				possibilities, randomized ice-cream / id numbers co-author, triangle 
				interior problem from topcoder, hal 9000 problem from topcoder,
				road layout from topcoder, implementing hide tags in YaBB, 
				worm propagation, polygon area
Don Barkauskas		error in prime pairs riddle: prime triples are ill-defined
Katherine Chan		japanese sangaku geometry I solution 
Jasvir Nagra		japanese sangaku geometry II solution in postscript, 100 prisoners and two bulbs
Tau Beta Pi (TBP)	for a few puzzle challenges
Eta Kappa Nu (HKN)	for many puzzle challenges and puzzle loving people
Danny Dulai  		eight queens
Samuel Vimes		nonhomogeneous ropes typo
Dipan K. Ghosh		twelve balls riddle
Eric Cole		twelve balls riddle
Louis Wainwright	guess number for money I
Ben Bardill		hospital elevator testing
Patrick Dreker		register value swap
Autumn Looijen		knight vs. dragon
Stephen Champailler	zeno's paradox's reference from godel, escher, bach
Christopher Kings-Lynne	coin unbiasing
Bart Samwel		fork in the road I clarification
Kannan Ramchandran	3-bit sensors; my EE research professor, also a riddle lover
Nick Yee		chocolate milk misphrasing, ghetto encryption I alternative phrasing
Steve Plimpton		chocolate milk misphrasing
Levsen Hendrik		chocolate milk misphrasing
Remco Hartog		broken clock, impatient patients
[I.M._Smarter_Enyu]	pop quiz
Philip Mock		8-way circle division
Michael Chang		uc berkeley in sf business district, coconut monkey typo
Jon Meilstrup		number spiral error
Ryan Russell		number spiral error, ones in a register solution
Matt Young		number spiral error
Jonathan Haas		robot collision programming, button trap generalization, smullyan was wrong				
Geoff Canyon		debastardization of stupid poem
Peter Surda		logical signs I unconventional analysis
Cory Ondrejka		anchor, add one without + or -; problems from game companies
Satish Rao		egg dropping, max sum in integer array; my CS170 (algorithms) professor
[gcooper]		what happened I
Andrew Blair		globe traversal confusing wording: cannot move in any direction you want
Ted Powell		error in family relations riddle; wording of 8 queens problem
Brave Sir Robin		moving bus direction
Eric Cole		new door scramble
J. A. H. Hunter		for making a problem that the bus passengers problem is modeled after
Sean R. Owen		sink the sub, repeated number rephrasing, shuffling cards
Andrew Glenn		sink the sub
Bruce Preston		calendar cubes II, with a beautiful GIF showing a solution 

Peter Ratiu		japanese sangaku geometry III solution, with AutoCAD screenshots
Michael Mendelsohn	japanese sangaku geometry III solution
Rob Mahurin		japanese sangaku geometry III solution
James Fingas		a very creative and amusing canuck. japanese sangaku geometry III solution, 
				willy's true colors, fork in the road III, love triangle, love square, 
				crazy sprinkler, cryptic address, finger gauges, cooperative checkers, 
				three primates, two gambling machines
Bryan Organ		japanese sangaku geometry III solution
Jeroen Rutten 		japanese sangaku geometry III solution
S. Montgomery-Smith	japanese sangaku geometry III solution
Marko Lukat		japanese sangaku geometry III solution, with beautiful .BMP diagram 

Eric Yeh		a genuine puzzle fanatic whom i'm overjoyed to have met. 
				past present future, generalization of egg dropping, generalization of 
				single file hat execution, coin flip game worth, envelope gamble II, 
				24 II, duck in pond, lion and tamer, 1000 wires, infinite checkerboard, 
				picard theorem proof that 0 = 1, gods of gibberland, operators of
				boolania, the puzzle forum, shuffling cards, forcefield detainment				
Nick Hobson		magnet detection, 24 III, 271, ant on a box, folded sheet of paper,
				farmer's enclosure, 2n+1 coins, two ladders, making a dollar, 
				sum of reciprocals, cyclic hexagon
			length of hypotenuse
Mike Lawther		27 cubes
Richard Feynman		sprinkler and pump
Douglas Hofstaeder	zeno's paradox tortoise and hare story
Dacher Keltner		ice cream urban riots; my psych 160 (social psych) professor
David Mace		tooth fairy company
[SAS]			chain link 21
Matthew Schultheis	placing trees
John Leen		analog clock III; one of my CS170 (algorithms) T.A.s
Andrew Ooi		party handshakes
Folkert Hindriks	hanging vs beheading
Steve Ragle		glass half full clarification: non-opaque sides, family relations 
				clarification: "dude" could be anyone
Daniel Filner		Joel Schumacher movie solution to what happened I
Karl Barrus		nth from end		
Misha Kruk		for loop tweaks (in three ways), excel simulator		
Keith Lloyd		chess puzzle I and II confusing wording: "attack" vs. "move to"
Dave Minott		222
Jette Randlov		all horses same color
Eric Winger		light bulb switches rephrasing
Tom VanCourt		anchor, balloon in car
Chris Seaton		desperados in jail
Mitchell Morris		ladder rungs
Michael Styer		racetrack laps
Zameer Andani		repeated number confusing wording

Jonathan Blow		storage algorithm solution
Jeff Thompson		storage algorithm solution
Jonathon Duerig		storage algorithm solution
Dan Hanson		storage algorithm solution
Gabriel Sechan		storage algorithm solution
Tom Saxton		storage algorithm solution
[HunterWare]		storage algorithm solution 
[alsee]			storage algorithm solution 
James Antill		storage algorithm solution

Tom Barringer		mean, median, neither solution: "median"
Bart Massey		mean, median, neither solution: "mean", ones in a register solution,
				storage algorithm demystification
David Krikorian		mean, median, neither solution: "neither"
Eric Sharkey		mean, median, neither solution: "neither"

[tudorb]		ones in a register solution
Kevin Day		ones in a register solution
Milan Ramaiya		ones in a register solution
Robert Merkel		ones in a register solution, fsck the marble jar system
James Jones		ones in a register solution
Haim Bitner		ones in a register solution
Adam Barth		ones in a register solution
Oscar Lazzarino		ones in a register solution
Damien Fisher		ones in a register solution
[DrkShadow]		ones in a register solution
Erik Blankendaal	ones in a register solution
Eric Smith		ones in a register solution

J.Demmel & J.Shewchuk	punchout cards, sweetheart mix tape
Alex Harris		nonconstructive p=np, super-villain transparencies, x^x
Michael Kelley		knight tours
[Mr._Martingale]	introductions all around
Kaisen Lin		3 enemies
Hakan Yilmaz		mean distance two points
Freddy Mercury		paper: "the best card trick", mathematical intelligencer 24 winter 2002
Justin Rising		how many stars in the universe, evil mayor
Marko Lukat		ladder into tower
William Kahan		four ghost ships, putnam exam problems
Jeremy Randolph		feminist rule
Michael Sinatra		slashdot effect traffic analysis
David Messerschmitt	every die face, circuit failure analysis
Patrick Masterson	dice corner, poison drinks, trees for willywutang, 
				single-instruction computer, hotel infinity
Frederik Bonte		kabouters
Randy Williams		train bridge
Pietro K.C.		2-sat to 2-col, partition, wine and water, gas stations, triangular numbers				
Chris Jackson		mystery matrix II
Brett Danaher		rumor spreading
Derek Abbott		two-girlfriends paradox
Ralph Boleslavsky	100 m race, positive matrix sums
Rui del-Negro		what happened II, what happened III, what happened IV
Jason Behrstock		bright and dark stars
[college math journal]	proof y equals zero (25 #1 Jan 1994 p.35)
[amer. math monthly]	rectangle into square (78 #7 Aug.-Sept. 1971.), 
				brick piercing (78 #7 aug-sept 1971)
Spyros Potamianos	coin biasing (variation of coin unbiasing)
Gary Hsieh		missing integer in array
[rec.puzzles]		high buildings and street vendors (11 Apr 1996)
Steven Rudich		good and bad computers 
Matt Lahut		relaying the good and bad computers riddle to me, loaded craps dice,
				penny track game, self-printing program, peg solitaire, jewel thieves
Richard Reti		chess study I, chess study II
Paul Sinclair		an ever-present source of wisdom, graciousness, and witty humor in the forums. trianglia II, all sigs are false, newcomb's dilemma, steiner ellipses, 10-adic numbers. thanks for all your contributions to maintaining the forum.
Tim Mann		perfect powers, obtuse triangles (martin gardner)
[ucb engineering news]	the clever grandfather, twiddling bolts
Luke Percival		positive matrix sums, card simulation
Richard M. Karp		knight circuit time, always ahead, calling a card's color
Anwis Das		infinite resistor network, closest point
Mike White		log motor
Louise Poon		stuck in a box
Jeffrey Wilhelm		remote control design
Anthony Cammon		conway sequence
[BNC]			for relaying the take the last chip puzzle to me, 
				acrobat thief and golden rope, century's last day, match puzzles,
				match equations, too many solutions, sum of real numbers
A.Frieze & D.Sleator	take the last chip
[SWF]			arrange the 13 pieces
T.Stevens & F.Wang	dog, chicken, rice
Danny P			dog, chicken, rice
Patrick Sesulka		money in book
[towr]			our most prolific forum poster :) dog, chicken, rice correction. wrote a very useful latex2png formula generator. thanks for all your work in maintaining the forum! 
Chi Sum Cheung		dog, chicken, rice correction
Brandon McPhail		topological rings
Andrew Gottelieb		what's the temperature outside
Ranjit Jhala		DFA design I: LR and RL products
Jacob Scott		stack indexing
David MacKay		corrected phrasing of several puzzles, three collinear points, erik's puzzle,
Eamon Warnock		impish pixie, ESP puzzles, chess game reconstruction, retrograde chess I,
(THUDandBLUNDER)			rope around the earth

Kozo Morimoto		two identical spheres
Abhijit Joshi 		samwise and gandalf
Devesh Parekh		php script for piping puzzles into mysql database
Amnon Melzer		path collision, bicycle tugging
Mary Lou			river crossing
Leonid Brouhkis		typewritter gibberish
Allistair Sinclair	oracle queries, quiz team scheduling, unrecognizable language
Mark Newheiser		elegantly greedy pirates
Joc Koelman			random points on sphere
Paul Jung			temperature antipodes
Aryabhatta			number of midpoints
Thomas Cover		convex set projection
Barukh				guessing cards suit, prolong the line
Nootch				dominant fifth
Eigenray			coloring the rational plane

Thanks to Contributors David Lau, Siddhartha Doshi, Jiong Shen, Carl Wang, Phoebus Chen, Alan Liu, Hansen Bow, Ernest Zhu, Elaine Lo, Yosen Lin, Don Barkauskas, Katherine Chan, Jasvir Nagra, Tau Beta Pi (TBP), Eta Kappa Nu (HKN), Danny Dulai, His Grace The Duke Of Ankh-Morpork Commander Sir Samuel Vimes, Michael Snyder, Dipan K. Ghosh, Eric Cole, Louis Wainwright, Ben Bardill, Patrick Dreker, Autumn Looijen, Stephen Champailler, Christopher Kings-Lynne, Bart Samwel, Kannan Ramchandran, Nick Yee, Steve Plimpton, Levsen Hendrik, Remco Hartog, [I.M._Smarter_Enyu], Philip Mock, Michael Chang, Jon Meilstrup, Ryan Russell, Matt Young, Jonathan Haas, Geoff Canyon, Peter Surda, Cory Ondrejka, Satish Rao, [gcooper], Ted Powell, Brave Sir Robin, Eric Cole, J. A. H. Hunter, Sean R. Owen, Andrew Glenn, Bruce Preston, Peter Ratiu, Michael Mendelsohn, Rob Mahurin, James Fingas, Bryan Organ, Jeroen Rutten, Stephen Montgomery-Smith, Marko Lukat, Eric Yeh, Nick Hobson, Mike Lawther, [anshil], Richard Feynman, Douglas Hofstaeder, Dacher Keltner, David Mace, [SAS], Matthew Schultheis, John Leen, Andrew Ooi, Folkert Hindriks, Steve Ragle, Daniel Filner, Karl Barrus, Misha Kruk, Keith Lloyd, Dave Minott, Jette Randlov, Eric Winger, Nathan Hellweg, Tom VanCourt, Chris Seaton, Mitchell Morris, Michael Styer, Zameer Andani, Jonathan Blow, Jeff Thompson, Jonathon Duerig, Dan Hanson, Gabriel Sechan, Tom Saxton, [HunterWare], [alsee], James Antill, Tom Barringer, Bart Massey, David Krikorian, Eric Sharkey, [tudorb], Kevin Day, Milan Ramaiya, Robert Merkel, James Jones, Haim Bitner, Adam Barth, Oscar Lazzarino, Damien Fisher, [DrkShadow], Erik Blankendaal, Eric Smith, James Demmel, Jonathan Shewchuk, Alex Harris, Michael Kelley, [Mr._Martingale], Kaisen Lin, Hakan Yilmaz, Freddy Mercury, Justin Rising, Marko Lukat, William Kahan, Jeremy Randolph, Michael Sinatra, David Messerschmitt, Patrick Masterson, Frederik Bonte, Randy Williams, Pietro K.C., Brett Danaher, Derek Abbott, Ralph Boleslavsky, Rui del-Negro, [college math journal], [amer. math monthly], Spyros Potamianos, Gary Hsieh, [rec.puzzles], Steven Rudich, Matt Lahut, Richard Reti, Paul Sinclair, Tim Mann, [ucb engineering news], Luke Percival, Anwis Das, Mike White, Louise Poon, Jeffrey Wilhelm, Anthony Cammon, [BNC], A.Frieze & D.Sleator, [SWF], Ted Stevens, Frank Wang, Danny P, Patrick Sesulka, [towr], Chi Sum Cheung, Ranjit Jhala, Jacob Scott, David McKay, Eamon Warnock (THUDandBLUNDER), Kozo Morimoto, Abhijit Joshi, Devesh Parekh, Amnon Melzer, Mary Lou, Leonid Brouhkis, Allistair Sinclair, Mark Newheiser, Joc Koelman, Paul Jung, Aryabhatta, Thomas Cover, Barukh, Nootch, Eigenray

William Wu © 2002-04: home | intro | easy | medium | hard | microsoft | cs | putnam | cigs | faq | pros | cons | laff | forum | credits