2 files changed, 61 insertions, 0 deletions
diff --git a/06/1.rkt b/06/1.rkt
new file mode 100644
index 0000000..5496476
--- /dev/null
+++ b/06/1.rkt
@@ -0,0 +1,32 @@
+#lang racket
+
+(define in (open-input-file "input"))
+
+(define (read-num-list)
+  (define line (read-line in))
+  (map
+   string->number
+   (string-split
+    (cadr (string-split (string-trim line) ":")))))
+
+(define times (read-num-list))
+(define distances (read-num-list))
+
+(define games (map cons times distances))
+
+(define (calc time hold-time)
+  (* hold-time (- time hold-time)))
+
+(define (solve time distance)
+  (define (loop counter hold-time)
+    (if (> hold-time time)
+        counter
+        (if (> (calc time hold-time) distance)
+            (loop (+ 1 counter) (+ 1 hold-time))
+            (loop counter (+ 1 hold-time)))))
+  (loop 0 0))
+
+(display (apply * (map
+                   (λ (x) (solve (car x) (cdr x)))
+                   games)))
+(newline)
diff --git a/06/2.rkt b/06/2.rkt
new file mode 100644
index 0000000..2d666ed
--- /dev/null
+++ b/06/2.rkt
@@ -0,0 +1,29 @@
+#lang racket
+
+(define in (open-input-file "input"))
+
+(define (read-num)
+  (define line (read-line in))
+  (string->number
+   (apply
+    string-append
+    (string-split
+     (cadr (string-split (string-trim line) ":"))))))
+
+(define time (read-num))
+(define distance (read-num))
+
+(define (calc time hold-time)
+  (* hold-time (- time hold-time)))
+
+(define (solve time distance)
+  (define (loop counter hold-time)
+    (if (> hold-time time)
+        counter
+        (if (> (calc time hold-time) distance)
+            (loop (+ 1 counter) (+ 1 hold-time))
+            (loop counter (+ 1 hold-time)))))
+  (loop 0 0))
+
+(display (solve time distance))
+(newline)