diff --git a/src/structured_data.clj b/src/structured_data.clj index ebfe1ce4..096f41ca 100644 --- a/src/structured_data.clj +++ b/src/structured_data.clj @@ -1,16 +1,18 @@ (ns structured-data) (defn do-a-thing [x] - :-) + (let [x2 (+ x x)] + (Math/pow x2 x2))) (defn spiff [v] - :-) + (+ (get v 0) (get v 2))) (defn cutify [v] - :-) + (conj v "<3")) (defn spiff-destructuring [v] - :-) + (let [[fst snd thd] v] + (+ fst thd))) (defn point [x y] [x y]) @@ -19,96 +21,115 @@ [bottom-left top-right]) (defn width [rectangle] - :-) + (let [[[x1 y1] [x2 y2]] rectangle] + (- x2 x1))) (defn height [rectangle] - :-) + (let [[[x1 y1] [x2 y2]] rectangle] + (- y2 y1))) (defn square? [rectangle] - :-) + (= (width rectangle) (height rectangle))) (defn area [rectangle] - :-) + (* (width rectangle) (height rectangle))) (defn contains-point? [rectangle point] - :-) + (let [[[x1 y1] [x2 y2]] rectangle + [x y] point] + (and (<= x1 x x2) (<= y1 y y2)))) (defn contains-rectangle? [outer inner] - :-) + (let [[p1 p2] inner] + (and (contains-point? outer p1) + (contains-point? outer p2)))) (defn title-length [book] - :-) + (count (:title book))) (defn author-count [book] - :-) + (count (:authors book))) (defn multiple-authors? [book] - :-) + (> (author-count book) 1)) (defn add-author [book new-author] - :-) + (assoc book :authors (conj (:authors book) new-author))) (defn alive? [author] - :-) + (not (contains? author :death-year))) (defn element-lengths [collection] - :-) + (map count collection)) (defn second-elements [collection] - :-) + (let [sec (fn [x] (first (rest x)))] + (map sec collection))) (defn titles [books] - :-) + (map :title books)) (defn monotonic? [a-seq] - :-) + (or (apply <= a-seq) + (apply >= a-seq))) (defn stars [n] - :-) + (apply str (repeat n \*))) (defn toggle [a-set elem] - :-) + (if (contains? a-set elem) + (disj a-set elem) + (conj a-set elem))) (defn contains-duplicates? [a-seq] - :-) + (not (= (count a-seq) (count (set a-seq))))) (defn old-book->new-book [book] - :-) + (assoc book :authors (set (:authors book)))) (defn has-author? [book author] - :-) + (contains? (:authors book) author)) (defn authors [books] - :-) + (apply clojure.set/union (map :authors books))) (defn all-author-names [books] - :-) + (set (map :name (authors books)))) (defn author->string [author] - :-) + (let [aname (:name author) + byear (:birth-year author) + dyear (:death-year author)] + (if (or byear dyear) + (apply str [aname " (" byear " - " dyear ")"]) + (str aname)))) (defn authors->string [authors] - :-) + (apply str (interpose ", " (map author->string authors)))) (defn book->string [book] - :-) + (apply str [(:title book) ", written by " (authors->string (:authors book))])) (defn books->string [books] - :-) + (let [nbooks (count books)] + (if (= 0 nbooks) "No books." + (str nbooks (if (= 1 nbooks) " book. " " books. ") + (apply str [(apply str (interpose ". " (map book->string books))) "."]))) + )) (defn books-by-author [author books] - :-) + (filter (fn [book] (has-author? book author)) books)) (defn author-by-name [name authors] - :-) + (first (filter (fn [author] (= name (:name author))) authors))) (defn living-authors [authors] - :-) + (filter (fn [author] (alive? author)) authors)) (defn has-a-living-author? [book] - :-) + (not (empty? (living-authors (:authors book))))) (defn books-by-living-authors [books] - :-) + (filter (fn [book] (has-a-living-author? book)) books)) ; %________%