start day22

2016/day22/lang.rkt

@@ -0,0 +1,33 @@
+#lang br/quicklang ;; http://adventofcode.com/2016/day/22
+(provide read-syntax
+         (rename-out [mb #%module-begin]))
+
+(define (read-syntax path port)
+  (strip-bindings
+   (let ([lines (string-split (port->string port) "\n")])
+     #`(module mod "lang.rkt"
+         #,@(for/list ([args (in-list (map string-split (cddr lines)))])
+              `(node ,@args))))))
+
+(define-macro (mb . NODES)
+  #'(#%module-begin
+     (define nodes (list . NODES))
+     (count-viable-pairs nodes)))
+
+(struct $node (pos used avail) #:transparent)
+    
+(define-macro (node NAME _ USED AVAIL _)
+  #'($node
+     (apply (λ(r i) (+ (string->number r)
+                       (* (string->number i) +i))) (regexp-match* #px"\\d+" NAME))
+     (string->number (string-trim USED "T"))
+     (string->number (string-trim AVAIL "T"))))
+(provide node)
+
+(define (count-viable-pairs nodes)
+  (for*/sum ([a (in-list nodes)]
+             [b (in-list nodes)]
+             #:when (and (not (zero? ($node-used a)))
+                         (not (equal? ($node-pos a) ($node-pos b)))
+                         (<= ($node-used a) ($node-avail b))))
+    1))

2016/day22/test.rkt

@@ -0,0 +1 @@
+#lang reader "lang.rkt"