camoy

Keybase proof

I hereby claim:

• I am camoy on github.
• I am camoy (https://keybase.io/camoy) on keybase.
• I have a public key whose fingerprint is CC10 FC49 A531 78CF 4DAA 0CAF 1CE9 059A 203F CAE1

To claim this, I am signing this object:

camoy

A logic puzzle called "Prize Box" from the ASCM problem solving competition:

Three boxes, 3 signs: Only one box has the prize; n is odd if and only if two signs are true. Sign A says "n is even and box 1 has the prize." Sign B says "n + 4 is a multiple of 3 or box 3 has the prize." Sign C says "n is odd or box 2 has the prize." Given that n is a single digit positive integer where every digit is equally likely, which

camoy

import qualified Data.Set.Monad as S

fix f init = until (\x -> x == f x) f init
close rstar = fix (\s -> s `S.union` (rstar s))
rstar g s = do { x <- s; (x, y) <- g; pure y }
reachable g = close (rstar g)

-- g1 = S.fromList [(1, 2), (2, 3), (3, 1), (4, 1)]
-- reachable g1 (S.singleton 1) == S.fromList [1, 2, 3]

camoy

(* This is an OCaml adaptation of (Y Y) Works! by Felleisen
   and Friedman. An updated version of the same essay is
   available in the Little Schemer, Chapter 9. To run the
   examples you have to enable the -rectypes flag. *)

(* Let's define the length function. *)

let rec length xs =
  match xs with
  | [] -> 0

camoy

(* Exercise: Write the class definition (no methods) for a linked list in
   Java. *)

(* Bad Approach:

   class List<T> {
     T data;
     List<T> next;
   }
 

camoy

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (assert pred)
  (or pred (amb)))

(define amb-queue (make-parameter #f))
(define amb-escape (make-parameter #f))

(define-syntax-rule (begin-amb fail body ...)
  (let/cc k

camoy

(define-values (success-tag fail-tag)
  (values (make-continuation-prompt-tag 'success)
          (make-continuation-prompt-tag 'fail)))

(define-syntax amb
  (syntax-rules ()
    [(_ alt ...)
     (call/comp
      (λ (k)
        (abort

camoy

let with_return f x =
  let r = ref None in
  try
    f (fun v -> r := (Some v); raise Not_found) x
  with _ ->
    match !r with
    | None -> raise Not_found
    | Some x -> x

let til_first_even =

camoy

#lang racket/base

(require racket/contract)

(define must-return/c
  (make-contract
   #:name 'must-return/c
   #:late-neg-projection
   (λ (blm)
     (λ (f neg)

camoy

#lang racket/base

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; provide

(provide violin)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; require