HAKMEM

M. Beeler [beeler@bbn.com]

R. W. Gosper [rwg@newton.macsyma.com]

R. Schroeppel [rcs@cs.arizona.edu]

Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program supported in part by the Advanced Research Projects Agency of the Department of Defense and monitored by the Office of Naval Research under Contract Number N00014-70-A-0362-0002.

Reproduction of this document, in whole or in part, is permitted for any purpose of the United States Government.

Compiled with the hope that a record of the random things people do around here can save some duplication of effort -- except for fun.

Here is some little known data which may be of interest to computer hackers. The items and examples are so sketchy that to decipher them may require more sincerity and curiosity than a non-hacker can muster. Doubtless, little of this is new, but nowadays it's hard to tell. So we must be content to give you an insight, or save you some cycles, and to welcome further contributions of items, new or used.

The classification of items into sections is even more illogical than necessary. This is because later elaborations tend to shift perspective on many items, and this elaboration will (hopefully) continue after publication, since this text is retained in "machinable" form. We forgive in advance anyone deterred by this wretched typography.

People referred to are from the A. I. Lab: Marvin Minsky [minsky@ai.mit.edu] Bill Gosper [rwg@newton.macsyma.com] Michael Beeler [beeler@bbn.com] Joe Cohen Jerry Freiberg John Roe Rich Schroeppel [rcs@cs.arizona.edu] David Silver Michael Speciner Richard Stallman [rms@ai.mit.edu] Gerald Sussman [gjs@ai.mit.edu] David Waltz Once at the A. I. Lab but now elsewhere: Jan Kok William Henneman Rici Liknaitzky George Mitchell Peter Samson Stuart Nelson Roger Banks Rollo Silver Mike Paterson [Mike.Paterson@dcs.warwick.ac.uk] at Digital Equipment Corporation: Jud Lenard Dave Plumer Ben Gurley (deceased) Steve Root elsewhere at M.I.T.: Gene Salamin PDP-1 hackers Eric Jensen Frances Yao Edward Fredkin once at M.I.T., but now elsewhere: Jackson Wright Steve Brown Malcolm Rayfield in France: Marco Schutzenberger Henry Cohen at Computer Corporation of America: Bill Mann at BBN: Robert Clements CAVEATS:

Some of this material is very inside -- many readers will have to excuse cryptic references.

The label "PROBLEM" does not always mean exercise; if no solution is given, it means we couldn't solve it. If you solve a problem in here, let us know.

Unless otherwise stated, all computer programs are in PDP-6/10 assembly language.

CONTENTS, HAKMEM 140

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