Task 1

3 files changed, 43 insertions, 2 deletions

diff --git a/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch-1.clj b/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch-1.clj
new file mode 120000
index 0000000000..924a7a086e
--- /dev/null
+++ b/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch-1.clj
@@ -0,0 +1 @@
+ch_1.clj
\ No newline at end of file
diff --git a/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch_1.clj b/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch_1.clj
new file mode 100644
index 0000000000..4ab609b3d8
--- /dev/null
+++ b/challenge-077/tyler-wardhaugh/clojure/src/tw/weekly/ch_1.clj
@@ -0,0 +1,39 @@
+(ns tw.weekly.ch-1
+  (:require [clojure.edn :as edn])
+  (:require [clojure.math.combinatorics :as combo]))
+
+;;; Task description (as of UPDATE: 2020-09-07 09:00:00)
+; You are given a positive integer $N.
+;
+; Write a script to find out all possible combination of Fibonacci Numbers required to get $N on addition.
+;
+; You are NOT allowed to repeat a number. Print 0 if none found.
+;;;
+
+; source: [Clojure High Performance Fibonacci – Deque](https://deque.blog/2017/06/01/clojure-high-performance-fibonacci/)]
+(defn fibo-lazy-seq
+  "Generate the nth Fibonacci Number, starting from 0, 1, 1, ..."
+  []
+  (letfn [(fibs [a b] (cons a (lazy-seq (fibs b (+ a b)))))]
+    (fibs 0N 1N)))
+
+(defn fibo-sum
+  "Find all combinations of Fibonacci Numbers that sum to n, returning nil if none are found."
+  [n]
+  (let [fibs (drop 2 (take n (fibo-lazy-seq)))
+        results (->> fibs
+                     combo/subsets
+                     (drop 1)       ; remove the empty subset, which is always first
+                     (filter #(= n (reduce + 0N %))))]
+    (seq results)))
+
+(defn -main
+  "Run Task 1 with a number N, defaulting to the number given in the task example, 6."
+  [& args]
+  (let [N (or (some-> args first edn/read-string) 6)
+        failure-result 0]
+    (if-let [results (fibo-sum N)]
+      (do
+        (printf "Found Fibonacci numbers that sum to %d:\n" N)
+        (dorun (map #(println (apply str (interpose " + " %))) results)))
+      (printf "No Fibonacci numbers sum to %d:\n%d\n" N failure-result))))
diff --git a/challenge-077/tyler-wardhaugh/clojure/test/tw/weekly/c77_test.clj b/challenge-077/tyler-wardhaugh/clojure/test/tw/weekly/c77_test.clj
index 8416dbe995..7ab39d517a 100644
--- a/challenge-077/tyler-wardhaugh/clojure/test/tw/weekly/c77_test.clj
+++ b/challenge-077/tyler-wardhaugh/clojure/test/tw/weekly/c77_test.clj
@@ -1,12 +1,13 @@
 (ns tw.weekly.c77-test
   (:require [clojure.test :refer :all]
             [clojure.java.io :as io]
-            [tw.weekly.ch-1 :refer []]
+            [tw.weekly.ch-1 :refer [fibo-sum]]
             [tw.weekly.ch-2 :refer []]))
 
 (deftest ch-1
   (testing "Task 1"
-    ))
+    (is (= #{(list 1N 2N 3N) (list 1N 5N)} (into #{} (fibo-sum 6))))
+    (is (= #{(list 1N 3N 5N) (list 1N 8N)} (into #{} (fibo-sum 9))))))
 
 (deftest ch-2
   (testing "Task 2"