-
-
Notifications
You must be signed in to change notification settings - Fork 33
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #24 from TheAlgorithms/fr33m0nk/add-immutable-dyna…
…mic-array-impl Adds immutable dynamic array impl
- Loading branch information
Showing
2 changed files
with
158 additions
and
145 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -1,85 +1,79 @@ | ||
| (ns data-structures.dynamic-array.core | ||
| (:refer-clojure :exclude [get set empty? remove pop])) | ||
| (:refer-clojure :exclude [get set empty? remove]) | ||
| (:import (clojure.lang RT))) | ||
|
|
||
| ;; See tests for the documentation on implementation | ||
| (defprotocol IDynamicArray | ||
| (get [this idx]) | ||
| (set [this idx value]) | ||
| (remove [this idx]) | ||
| (empty? [this]) | ||
| (length [this]) | ||
| (next-idx [this]) | ||
| (append [this value]) | ||
| (pop [this])) | ||
|
|
||
| (deftype DynamicArray [^:unsynchronized-mutable length | ||
| ^:unsynchronized-mutable next-idx | ||
| ^:unsynchronized-mutable array] | ||
| IDynamicArray | ||
| (get [_ idx] | ||
| (assert (< -1 idx next-idx) "Invalid index value supplied") | ||
| (aget array idx)) | ||
| (set [_ idx value] | ||
| (assert (<= 0 idx) "Invalid index value supplied") | ||
| (when (or (= next-idx length) (> idx length)) | ||
| (let [next-length (* idx 2) | ||
| next-array (make-array Integer/TYPE next-length)] | ||
| (doseq [i (range length)] | ||
| (->> (aget array i) | ||
| (aset next-array i))) | ||
| (set! array next-array) | ||
| (set! length next-length))) | ||
| (aset array next-idx value) | ||
| (set! next-idx (inc idx)) | ||
| idx) | ||
| (remove [_ idx] | ||
| (assert (< -1 idx next-idx) "Invalid index value supplied") | ||
| (let [next-next-idx (dec next-idx) | ||
| popped-element (aget array idx)] | ||
| (doseq [dest-idx (range idx next-idx) | ||
| :let [source-idx (inc dest-idx)] | ||
| :when (not= source-idx length)] | ||
| (aset array dest-idx (aget array source-idx))) | ||
| (set! next-idx next-next-idx) | ||
| popped-element)) | ||
| (empty? [_] | ||
| (zero? next-idx)) | ||
| (length [_] | ||
| (alength array)) | ||
| (next-idx [this] | ||
| next-idx) | ||
| (append [_ value] | ||
| (when (= next-idx length) | ||
| (let [next-length (* length 2) | ||
| next-array (make-array Integer/TYPE next-length)] | ||
| (doseq [i (range length)] | ||
| (->> (aget array i) | ||
| (aset next-array i))) | ||
| (set! array next-array) | ||
| (set! length next-length))) | ||
| (let [old-capacity next-idx] | ||
| (aset array next-idx value) | ||
| (set! next-idx (inc next-idx)) | ||
| old-capacity)) | ||
| (pop [_] | ||
| (assert (> next-idx 0) "Nothing to pop") | ||
| (let [next-next-idx (dec next-idx) | ||
| popped-element (aget array next-next-idx)] | ||
| (aset array next-next-idx 0) | ||
| (set! next-idx next-next-idx) | ||
| popped-element)) | ||
| Object | ||
| (toString [_] | ||
| (let [^StringBuilder sb (StringBuilder.)] | ||
| (.append sb "[ ") | ||
| (doseq [i (range next-idx)] | ||
| (.append sb (aget array i)) | ||
| (.append sb " ")) | ||
| (.append sb "]") | ||
| (.toString sb)))) | ||
|
|
||
| (defn ->DynamicArray | ||
| [initial-capacity] | ||
| (when (>= 0 initial-capacity) | ||
| (throw (IllegalArgumentException. "Invalid initial capacity"))) | ||
| (DynamicArray. initial-capacity 0 (make-array Integer/TYPE initial-capacity))) | ||
| [initial-capacity []]) | ||
|
|
||
| (defn capacity | ||
| [dynamic-array] | ||
| (let [[cap _] dynamic-array] | ||
| cap)) | ||
|
|
||
| (defn length | ||
| [dynamic-array] | ||
| (let [[_ store] dynamic-array] | ||
| (count store))) | ||
|
|
||
| (defn empty? | ||
| [dynamic-array] | ||
| (zero? (length dynamic-array))) | ||
|
|
||
| (defn get | ||
| [dynamic-array idx] | ||
| (assert (< -1 idx (length dynamic-array)) "Invalid index value supplied") | ||
| (let [[_ store] dynamic-array] | ||
| (nth store idx))) | ||
|
|
||
| (defn set | ||
| [dynamic-array idx value] | ||
| (assert (<= 0 idx) "Invalid index value supplied") | ||
| (let [[capacity store] dynamic-array] | ||
| (if (< idx (dec capacity)) | ||
| [capacity (assoc store idx value)] | ||
| [(* 2 (inc idx)) (into [] | ||
| cat | ||
| [store | ||
| (vec (repeat (- idx (count store)) nil)) | ||
| [value]])]))) | ||
|
|
||
| (defn remove | ||
| [dynamic-array idx] | ||
| (assert (< -1 idx (length dynamic-array)) "Invalid index value supplied") | ||
| (let [[capacity store] dynamic-array] | ||
| [capacity (into [] | ||
| cat | ||
| [(subvec store 0 idx) | ||
| (subvec store (inc idx))])])) | ||
|
|
||
| (defn next-idx | ||
| [dynamic-array] | ||
| (length dynamic-array)) | ||
|
|
||
| (defn append | ||
| [dynamic-array value] | ||
| (let [[capacity store] dynamic-array] | ||
| (if (not= capacity (count store)) | ||
| [capacity (conj store value)] | ||
| [(* 2 capacity) (conj store value)]))) | ||
|
|
||
| (defn pop-array | ||
| [dynamic-array] | ||
| (assert (not (empty? dynamic-array)) "Nothing to pop") | ||
| (let [[capacity store] dynamic-array] | ||
| [capacity (pop store)])) | ||
|
|
||
| (defn to-string | ||
| [dynamic-array] | ||
| (let [^StringBuilder sb (StringBuilder.)] | ||
| (.append sb "[ ") | ||
| (doseq [i (range (length dynamic-array))] | ||
| (.append sb (get dynamic-array i)) | ||
| (.append sb " ")) | ||
| (.append sb "]") | ||
| (.toString sb))) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters