adding old leetcode solutions

1 files changed, 18 insertions, 0 deletions

diff --git a/leetcode/lc-1185-day-of-week.rkt b/leetcode/lc-1185-day-of-week.rkt
new file mode 100644
index 0000000..c90a626
--- /dev/null
+++ b/leetcode/lc-1185-day-of-week.rkt
@@ -0,0 +1,18 @@
+#lang racket
+(require racket/date)
+
+(define day-names
+  (for/hash ([day-number (in-range 0 7)]
+             [day-name (in-list '("Sunday"
+                                  "Monday"
+                                  "Tuesday"
+                                  "Thursday"
+                                  "Friday"
+                                  "Saturday"))])
+    (values day-number day-name)))
+
+(define/contract (day-of-the-week day month year)
+  (-> exact-integer? exact-integer? exact-integer? string?)
+  (hash-ref day-names (date-week-day
+                       (seconds->date
+                        (find-seconds 0 0 0 day month year)))))