Ch106 (Clojure): Tasks 1 & 2

7 files changed, 113 insertions, 6 deletions

diff --git a/challenge-106/tyler-wardhaugh/clojure/README.md b/challenge-106/tyler-wardhaugh/clojure/README.md
index 469eabb6cb..4ad284eaa5 100644
--- a/challenge-106/tyler-wardhaugh/clojure/README.md
+++ b/challenge-106/tyler-wardhaugh/clojure/README.md
@@ -1,13 +1,13 @@
-# tw.weekly.c105
+# tw.weekly.c106
 
 
-The Weekly Challenge - #105 - Tyler Wardhaugh
+The Weekly Challenge - #106 - Tyler Wardhaugh
 
 ## Usage
 
 Run the project directly (shows default output from both tasks):
 
-    $ clojure -M -m tw.weekly.c105.core
+    $ clojure -M -m tw.weekly.c106.core
 
 Run the project's tests (which are samples from the task descriptions):
 
@@ -15,11 +15,11 @@ Run the project's tests (which are samples from the task descriptions):
 
 Run Task #1 with input
 
-    $ clojure -M -m tw.weekly.c105.t1 N K
+    $ clojure -M -m tw.weekly.c106.t1 N
 
 Run Task #2 with input:
 
-    $ clojure -M -m tw.weekly.c105.t2 NAME
+    $ clojure -M -m tw.weekly.c106.t2 N D
 
 ## Project Template
 
diff --git a/challenge-106/tyler-wardhaugh/clojure/deps.edn b/challenge-106/tyler-wardhaugh/clojure/deps.edn
index 32772ee93c..8b94f9a032 100644
--- a/challenge-106/tyler-wardhaugh/clojure/deps.edn
+++ b/challenge-106/tyler-wardhaugh/clojure/deps.edn
@@ -1,6 +1,5 @@
 {:paths ["src" "resources"]
  :deps {org.clojure/clojure {:mvn/version "1.10.1"}
-        org.apache.commons/commons-math3 {:mvn/version "3.6.1"}
         org.clojure/math.numeric-tower {:mvn/version "0.0.4"}}
  :aliases
  {:test {:extra-paths ["test"]
diff --git a/challenge-106/tyler-wardhaugh/clojure/pom.xml b/challenge-106/tyler-wardhaugh/clojure/pom.xml
index b6737dd838..ba1826c36c 100644
--- a/challenge-106/tyler-wardhaugh/clojure/pom.xml
+++ b/challenge-106/tyler-wardhaugh/clojure/pom.xml
@@ -30,6 +30,11 @@
       <artifactId>clojure</artifactId>
       <version>1.10.1</version>
     </dependency>
+    <dependency>
+      <groupId>org.clojure</groupId>
+      <artifactId>math.numeric-tower</artifactId>
+      <version>0.0.4</version>
+    </dependency>
   </dependencies>
   <build>
     <sourceDirectory>src</sourceDirectory>
diff --git a/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/core.clj b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/core.clj
new file mode 100644
index 0000000000..d6c8034916
--- /dev/null
+++ b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/core.clj
@@ -0,0 +1,12 @@
+(ns tw.weekly.c106.core
+  (:require [tw.weekly.c106.t1 :as t1])
+  (:require [tw.weekly.c106.t2 :as t2])
+  (:gen-class))
+
+(defn -main
+  "Run all tasks"
+  [& _]
+  (println "Task #1:")
+  (t1/-main)
+  (println "\nTask #2:")
+  (t2/-main))
diff --git a/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t1.clj b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t1.clj
new file mode 100644
index 0000000000..fefdbafb79
--- /dev/null
+++ b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t1.clj
@@ -0,0 +1,22 @@
+(ns tw.weekly.c106.t1
+  (:require [clojure.edn :as edn]))
+
+;;;
+; Task description for TASK #1 › Maximum Gap
+;;;
+(def DEFAULT-INPUT [2 9 3 5])
+
+(defn maximum-gap
+  "Determine the maximum difference between two successive elements once coll
+  is sorted."
+  [coll]
+  (let [source (->> (sort coll) (partition 2 1))
+        xf (map (fn [[x y]] (- y x)))]
+    (transduce xf max 0 source)))
+
+(defn -main
+  "Run Task 1 with a given N, defaulting to the example given in the task
+  description."
+  [& args]
+  (let [N (or (some-> args first edn/read-string) DEFAULT-INPUT)]
+    (println (maximum-gap N))))
diff --git a/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t2.clj b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t2.clj
new file mode 100644
index 0000000000..d48c6e3b0e
--- /dev/null
+++ b/challenge-106/tyler-wardhaugh/clojure/src/tw/weekly/c106/t2.clj
@@ -0,0 +1,43 @@
+(ns tw.weekly.c106.t2
+  (:require [clojure.edn :as edn]
+            [clojure.math.numeric-tower :refer [abs]]))
+
+;;;
+; Task description for TASK #2 › Decimal String
+;;;
+(def DEFAULT-INPUT [1 3])
+
+(defn- decimal-string-recurring
+  "Covert the given n[umerator] and d[enominator] (which must be known to
+  have a recurring fractional result) into a decimal string where the recurring
+  fractional is put in parenthesis."
+  [n d]
+  (loop [remainder (abs (rem n d))
+         cache {}
+         result []]
+    (if (not (or (zero? remainder) (cache remainder)))
+      (recur (rem (* 10 remainder) d)
+             (assoc cache remainder (count (apply str result)))
+             (conj result (quot (* 10 remainder) d)))
+      (let [[lead recurrence] (->> result (split-at (get cache remainder 0)))
+            whole (quot n d)
+            pieces (concat [whole \.] lead [\(] recurrence [\)])]
+        (apply str pieces)))))
+
+(defn decimal-string
+  "Covert the given n[umerator] and d[enominator] into a decimal string where any
+  recurring fractional is put in parenthesis."
+  [n d]
+  (try (str (/ (bigdec n) d))
+       (catch ArithmeticException _
+         ; BigDecimal throws this exception when the result cannot be
+         ; represented with the 'UNLIMITED' precision (the default), i.e.,
+         ; there is a recurring fractional result
+         (decimal-string-recurring n d))))
+
+(defn -main
+  "Run Task 2 with a given N and D, defaulting to the example given in the task
+  description."
+  [& args]
+  (let [[N D] (or (some->> args (take 2) (map edn/read-string)) DEFAULT-INPUT)]
+    (println (decimal-string N D))))
diff --git a/challenge-106/tyler-wardhaugh/clojure/test/tw/weekly/c106_test.clj b/challenge-106/tyler-wardhaugh/clojure/test/tw/weekly/c106_test.clj
new file mode 100644
index 0000000000..dad33dfd06
--- /dev/null
+++ b/challenge-106/tyler-wardhaugh/clojure/test/tw/weekly/c106_test.clj
@@ -0,0 +1,26 @@
+(ns tw.weekly.c106-test
+  (:require [clojure.test :refer [deftest is testing]]
+            [tw.weekly.c106.t1 :refer [maximum-gap]]
+            [tw.weekly.c106.t2 :refer [decimal-string]]))
+
+(deftest task-1
+  (testing "Task 1, Maximum Gap"
+    (is (= 4 (maximum-gap [2, 9, 3, 5])))
+    (is (= 5 (maximum-gap [1, 3, 8, 2, 0])))
+    (is (= 0 (maximum-gap [5])))))
+
+; additional test cases pulled from other submissions
+(deftest task-2
+  (testing "Task 2, Decimal String"
+   (is (= "0.(3)" (decimal-string 1 3)))
+   (is (= "0.5" (decimal-string 1 2)))
+   (is (= "0.0(75)" (decimal-string 5 66)))
+   (is (= "-3.(142857)" (decimal-string -22 7)))
+   (is (= "-0.375" (decimal-string 3 -8)))
+   (is (= "-11" (decimal-string -99 9)))
+   (is (= "0.(010309278350515463917525773195876288659793814432989690721649484536082474226804123711340206185567)"
+          (decimal-string 1 97)))
+   (is (= "5.(210084033613445378151260504201680672268907563025)"
+          (decimal-string 620 119)))
+   (is (= "0.0001(6)" (decimal-string 1 6000)))
+   (is (= "0.(0196078431372549)" (decimal-string 1 51)))))