day08: add part 1

README.md

@@ -9,3 +9,4 @@
 | **5** |         |        | ✅     |     |
 | **6** |         |        |        | ✅  |
 | **7** | ✅      |        |        |     |
+| **8** | part 1  |        |        |     |

day08.scm

@@ -0,0 +1,24 @@
+(import (chicken io))
+(import (chicken string))
+(import (chicken format))
+(import srfi-1)
+
+(define (summap a b) (foldl + 0 (map a b)))
+
+(define (displayln x) (format #t "~s~%" x))
+
+(define (split-line line)
+  (let ((halves (string-split line "|")))
+    (map string-split halves)))
+
+(define (is-1478 pattern)
+  (let ((len (string-length pattern)))
+    (not (or (eq? len 5) (eq? len 6)))))
+
+(define (count-1478 parsed)
+  (let-values (((patterns output) (apply values parsed)))
+    (count is-1478 output)))
+
+(let* ((lines (read-lines))
+       (separated (map split-line lines)))
+  (displayln (summap count-1478 separated)))