prep for 2023, renaming for consistency

1 files changed, 36 insertions, 0 deletions

diff --git a/aoc2022/day-07/day-07.rkt b/aoc2022/day-07/day-07.rkt
new file mode 100644
index 0000000..3826cc4
--- /dev/null
+++ b/aoc2022/day-07/day-07.rkt
@@ -0,0 +1,36 @@
+#lang racket
+
+(require advent-of-code
+         fancy-app
+         threading
+         (only-in relation ->number))
+
+(define command-output (~> (fetch-aoc-input (find-session) 2022 7) (string-split "\n")))
+
+(define (parse-commands cmds)
+  (define (update-sizes h path size)
+    (match path
+      ['() h]
+      [(list* _ fs) (update-sizes (hash-update h path (+ _ size) 0) fs size)]))
+
+  (for/fold ([folders (hash)] [current-path '()] [previously-seen? #false] #:result folders)
+            ([cmd (in-list cmds)])
+    (match (string-split cmd)
+      [(list "$" "ls") (values folders current-path (hash-has-key? folders current-path))]
+      [(list "$" "cd" "/") (values folders '("/") #false)]
+      [(list "$" "cd" "..") (values folders (rest current-path) #false)]
+      [(list "$" "cd" folder) (values folders (cons folder current-path) #false)]
+      [(list "dir" _) (values folders current-path previously-seen?)]
+      [(list (app ->number size) _)
+       (cond
+         [previously-seen? (values folders current-path previously-seen?)]
+         [else (values (update-sizes folders current-path size) current-path previously-seen?)])])))
+
+(define folders (parse-commands command-output))
+
+;; part 1
+(for/sum ([(_ v) (in-hash folders)] #:when (<= v 100000)) v)
+
+;; part 2
+(define required-to-delete (- 30000000 (- 70000000 (hash-ref folders '("/")))))
+(~>> folders hash-values (filter (> _ required-to-delete)) (apply min))