From a2d11e568871928979a81a25b0c79d7fa73f006d Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Sun, 17 Dec 2017 21:37:42 -0800
Subject: [PATCH] d18 s1

---
 2017/d18/main.rkt  | 31 +++++++++++++++++++++++++++++++
 2017/d18/star1.rkt | 42 ++++++++++++++++++++++++++++++++++++++++++
 2017/d18/test1.rkt | 11 +++++++++++
 3 files changed, 84 insertions(+)
 create mode 100644 2017/d18/main.rkt
 create mode 100644 2017/d18/star1.rkt
 create mode 100644 2017/d18/test1.rkt

diff --git a/2017/d18/main.rkt b/2017/d18/main.rkt
new file mode 100644
index 0000000..ec2bfb4
--- /dev/null
+++ b/2017/d18/main.rkt
@@ -0,0 +1,31 @@
+#lang reader "../aoc-lang.rkt"
+(provide (rename-out [#%mb #%module-begin]) ★ ★★)
+
+(define-macro (#%mb (STARS) TOKS ...)
+  #`(#%module-begin
+     (time (STARS (vector (λ () TOKS) ...)))))
+
+(define regs (make-hasheq))
+(define last-sound-played (make-parameter #f))
+(struct offset-signal (val))
+(struct end-signal (val))
+
+(provide snd set add mul mod rcv jgz)
+(define-macro (value VAL) #'(let ([val 'VAL]) (if (number? val) val (hash-ref regs val))))
+(define-macro (snd REG) #'(last-sound-played (hash-ref regs 'REG)))
+(define-macro (set REG VAL) #'(hash-set! regs 'REG (value VAL)))
+(define-macro (add REG VAL) #'(hash-update! regs 'REG (λ (val) (+ val (value VAL))) 0))
+(define-macro (mul REG VAL) #'(hash-update! regs 'REG (λ (val) (* val (value VAL))) 0))
+(define-macro (mod REG VAL) #'(hash-update! regs 'REG (λ (val) (modulo val (value VAL))) 0))
+(define-macro (rcv REG) #'(unless (zero? (hash-ref regs 'REG)) (raise (last-sound-played))))
+(define-macro (jgz REG VAL) #'(when (positive? (hash-ref regs 'REG)) (raise (offset-signal (value VAL)))))
+
+(define (★ insts)
+  (with-handlers ([number? values])
+    (for/fold ([offset 0])
+              ([i (in-naturals)])
+      (with-handlers ([offset-signal? (λ (os) (+ (offset-signal-val os) offset))])
+        (define proc (vector-ref insts offset))
+        (proc)
+        (add1 offset)))))
+  
\ No newline at end of file
diff --git a/2017/d18/star1.rkt b/2017/d18/star1.rkt
new file mode 100644
index 0000000..0e8a9e0
--- /dev/null
+++ b/2017/d18/star1.rkt
@@ -0,0 +1,42 @@
+#lang reader "main.rkt" ★
+set i 31
+set a 1
+mul p 17
+jgz p p
+mul a 2
+add i -1
+jgz i -2
+add a -1
+set i 127
+set p 464
+mul p 8505
+mod p a
+mul p 129749
+add p 12345
+mod p a
+set b p
+mod b 10000
+snd b
+add i -1
+jgz i -9
+jgz a 3
+rcv b
+jgz b -1
+set f 0
+set i 126
+rcv a
+rcv b
+set p a
+mul p -1
+add p b
+jgz p 4
+snd a
+set a b
+jgz 1 3
+snd b
+set f 1
+add i -1
+jgz i -11
+snd a
+jgz f -16
+jgz a -19
\ No newline at end of file
diff --git a/2017/d18/test1.rkt b/2017/d18/test1.rkt
new file mode 100644
index 0000000..50805d0
--- /dev/null
+++ b/2017/d18/test1.rkt
@@ -0,0 +1,11 @@
+#lang reader "main.rkt" ★ ; 4
+set a 1
+add a 2
+mul a a
+mod a 5
+snd a
+set a 0
+rcv a
+jgz a -1
+set a 1
+jgz a -2
\ No newline at end of file