Merge pull request #3907 from tylerw/tw/challenge-108

Ch108 (Clojure): Tasks 1 & 2

5 files changed, 72 insertions, 2 deletions

diff --git a/challenge-108/tyler-wardhaugh/clojure/deps.edn b/challenge-108/tyler-wardhaugh/clojure/deps.edn
index a781a94ba4..ab21fb11e4 100644
--- a/challenge-108/tyler-wardhaugh/clojure/deps.edn
+++ b/challenge-108/tyler-wardhaugh/clojure/deps.edn
@@ -10,5 +10,5 @@
    :main-opts ["-m" "cognitect.test-runner"
                "-d" "test"]}
   :uberjar {:extra-deps {seancorfield/depstar {:mvn/version "1.0.99"}}
-            :main-opts ["-m" "hf.depstar.uberjar" "tw.weekly.c102.jar"
-                        "-C" "-m" "tw.weekly.c102"]}}}
+            :main-opts ["-m" "hf.depstar.uberjar" "tw.weekly.c108.jar"
+                        "-C" "-m" "tw.weekly.c108"]}}}
diff --git a/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/core.clj b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/core.clj
new file mode 100644
index 0000000000..fbdfb2fc07
--- /dev/null
+++ b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/core.clj
@@ -0,0 +1,12 @@
+(ns tw.weekly.c108.core
+  (:require [tw.weekly.c108.t1 :as t1])
+  (:require [tw.weekly.c108.t2 :as t2])
+  (:gen-class))
+
+(defn -main
+  "Run all tasks"
+  [& _]
+  (println "Task #1:")
+  (t1/-main)
+  (println "\nTask #2:")
+  (t2/-main))
diff --git a/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t1.clj b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t1.clj
new file mode 100644
index 0000000000..60c7f2feeb
--- /dev/null
+++ b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t1.clj
@@ -0,0 +1,14 @@
+(ns tw.weekly.c108.t1
+  (:require [clojure.pprint :refer [cl-format]]))
+
+;;;
+; Task description for TASK #1 › Locate Memory
+;;;
+
+(def myvar 0)
+
+(defn -main
+  "Run Task 1."
+  [& _]
+  (let [hashcode (System/identityHashCode myvar)]
+    (cl-format true "~a: value=~a hashcode=~a~%" #'myvar myvar hashcode)))
diff --git a/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t2.clj b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t2.clj
new file mode 100644
index 0000000000..5f6795096f
--- /dev/null
+++ b/challenge-108/tyler-wardhaugh/clojure/src/tw/weekly/c108/t2.clj
@@ -0,0 +1,37 @@
+(ns tw.weekly.c108.t2
+  (:require [clojure.edn :as edn]
+            [clojure.pprint :refer [cl-format]]))
+
+;;;
+; Task description for TASK #2 › Bell Numbers
+;;;
+(def DEFAULT-INPUT 10)
+
+;;;
+; translation of:
+;   (Haskell)
+;   a011971 n k = a011971_tabl !! n !! k
+;   a011971_row n = a011971_tabl !! n
+;   a011971_tabl = iterate (\row -> scanl (+) (last row) row) [1]
+; source:
+;   https://oeis.org/A011971
+;     Aitken's array: triangle of numbers {a(n,k), n >= 0, 0 <= k <= n} read by
+;     rows, defined by a(0,0)=1, a(n,0) = a(n-1,n-1), a(n,k) = a(n,k-1) +
+;     a(n-1,k-1).
+; linked from:
+;   https://oeis.org/A000110
+;     Bell or exponential numbers: number of ways to partition a set of n
+;     labeled elements.
+;;;
+(defn bell-numbers
+  "Return a list of the first n Bell Numbers"
+  [n]
+  (let [f (fn [row] (reductions + (last row) row))
+        table (concat [[1]] (take (dec n) (iterate f [1])))]
+    (sequence (map last) table)))
+
+(defn -main
+  "Run Task 2 with a given CLASSNAME, defaulting to a standard Java class"
+  [& args]
+  (let [N (or (some-> args first edn/read-string) DEFAULT-INPUT)]
+    (cl-format true "~{~a~^, ~}~%" (bell-numbers N))))
diff --git a/challenge-108/tyler-wardhaugh/clojure/test/tw/weekly/c108_test.clj b/challenge-108/tyler-wardhaugh/clojure/test/tw/weekly/c108_test.clj
new file mode 100644
index 0000000000..c91d5e687e
--- /dev/null
+++ b/challenge-108/tyler-wardhaugh/clojure/test/tw/weekly/c108_test.clj
@@ -0,0 +1,7 @@
+(ns tw.weekly.c108-test
+  (:require [clojure.test :refer [deftest is testing]]
+            [tw.weekly.c108.t2 :refer [bell-numbers]]))
+
+(deftest task-2
+  (testing "Task 2 Bell Numbers"
+    (is (= [1 1 2 5 15 52 203 877 4140 21147] (bell-numbers 10)))))