- html - 出于某种原因,IE8 对我的 Sass 文件中继承的 html5 CSS 不友好?
- JMeter 在响应断言中使用 span 标签的问题
- html - 在 :hover and :active? 上具有不同效果的 CSS 动画
- html - 相对于居中的 html 内容固定的 CSS 重复背景?
剧透警告,这是 Code Day 6 降临的第一部分。
我试图解决 this Clojure 和 Scala 中的问题。 Scala 程序运行良好,并在我的 Macbook Air 上几秒钟内完成。然而,Clojure 版本需要更长的时间。这里有什么问题?
(ns adventofcode.day6
(:require [clojure.java.io :as io]
[clojure.string :as string]))
(set! *warn-on-reflection* true)
(def ^:const grid-size 1000)
(defn make-grid []
(let [grid (make-array Long/TYPE grid-size grid-size)]
(doseq [i (range grid-size)
j (range grid-size)]
(aset grid i j -1))
grid))
(defn parse-line [l]
(let [[command left-top right-bottom]
(-> l
(string/replace "turn off" "turn-off")
(string/replace "turn on" "turn-on")
(string/replace "through " "")
(string/split #" "))
parse-coordinates (fn [s]
(let [parts (string/split s #",")]
(map #(Integer/parseInt %) parts)))
[left top] (parse-coordinates left-top)
[right bottom] (parse-coordinates right-bottom)]
[command left top right bottom]))
(defn process-line [grid command left top right bottom]
(doseq [i (range left (inc right))
j (range top (inc bottom))]
(case command
"turn-off" (aset grid i j -1)
"turn-on" (aset grid i j 1)
"toggle" (aset grid i j (* -1 (aget grid i j)))
(throw (Exception. "unrecognized command")))))
(defn count-lights [grid]
(reduce + (for [i (range grid-size)
j (range grid-size)
:let [value (aget grid ^Long i ^Long j)]
:when (pos? value)]
value)))
(defn the-answer []
(with-open [rdr (-> "input-day6.txt"
io/resource
io/reader)]
(let [grid (make-grid)]
(doseq [l (line-seq rdr)]
(apply process-line grid
(parse-line l)))
(count-lights grid))))
(ns adventofcode.day6faster
(:require [clojure.java.io :as io]
[clojure.string :as string]))
(set! *warn-on-reflection* true)
(def ^:const grid-size 1000)
(defn make-grid []
(vec (repeat (* grid-size grid-size) -1)))
(defn parse-line [l]
(let [[command left-top right-bottom]
(-> l
(string/replace "turn off" "turn-off")
(string/replace "turn on" "turn-on")
(string/replace "through " "")
(string/split #" "))
parse-coordinates (fn [s]
(let [parts (string/split s #",")]
(map #(Integer/parseInt %) parts)))
[left top] (parse-coordinates left-top)
[right bottom] (parse-coordinates right-bottom)]
[command left top right bottom]))
(defn set-grid! [t-grid grid-size i j v]
(let [pos (+ i (* j (dec grid-size)))]
(assoc! t-grid pos v)))
(defn update-grid! [t-grid grid-size i j f]
(let [pos (+ i (* j (dec grid-size)))]
(assoc! t-grid pos
(f (get t-grid pos)))))
(defn process-line [t-grid command left top right bottom]
(doseq [i (range left (inc right))
j (range top (inc bottom))]
(case command
"turn-off" (set-grid! t-grid grid-size i j -1)
"turn-on" (set-grid! t-grid grid-size i j 1)
"toggle" (update-grid! t-grid grid-size i j (fn [i] (* -1 i)))
(throw (Exception. "unrecognized command")))))
(defn count-lights [grid]
(count (filter pos? grid)))
(defn the-answer []
(with-open [rdr (-> "input-day6.txt"
io/resource
io/reader)]
(let [t-grid (transient (make-grid))]
(doseq [l (line-seq rdr)]
(apply process-line t-grid
(parse-line l)))
(count-lights (persistent! t-grid)))))
(ns adventofcode.day6singlearray
(:require [clojure.java.io :as io]
[clojure.string :as string]))
(set! *warn-on-reflection* true)
(set! *unchecked-math* :warn-on-boxed)
(def ^:const grid-size 1000)
(defn make-grid []
(let [l (* grid-size grid-size)
a (make-array Long/TYPE l)]
(loop [i 0]
(if (< i l)
(do (aset ^longs a i -1)
(recur (inc i)))
a))))
(defn parse-line [l]
(let [[command left-top right-bottom]
(-> l
(string/replace "turn off" "turn-off")
(string/replace "turn on" "turn-on")
(string/replace "through " "")
(string/split #" "))
parse-coordinates (fn [s]
(let [parts (string/split s #",")]
(map #(Integer/parseInt %) parts)))
[left top] (parse-coordinates left-top)
[right bottom] (parse-coordinates right-bottom)]
[command left top right bottom]))
(defn set-grid! [grid ^long i ^long j v]
(let [pos (+ i (* j (dec grid-size)))]
(aset ^longs grid pos ^long v)))
(defn toggle-grid! [grid ^long i ^long j]
(let [pos (+ i (* j (dec grid-size)))]
(aset ^longs grid pos
^long (* -1 (aget ^longs grid pos)))))
(defn process-line [grid command left top right bottom]
(let [operation (case command
"turn-off" #(set-grid! grid %1 %2 -1)
"turn-on" #(set-grid! grid %1 %2 1)
"toggle" #(toggle-grid! grid %1 %2)
(throw (Exception. "unrecognized command")))]
(loop [^long i left
^long j top]
(if (<= i ^long right)
(if (<= j ^long bottom)
(do (operation i j)
(recur i (inc j)))
(recur (inc i) top))))))
(defn count-lights [grid]
(count (filter pos? grid)))
(defn the-answer []
(with-open [rdr (-> "input-day6.txt"
io/resource
io/reader)]
(let [grid (make-grid)]
(doseq [l (line-seq rdr)]
(apply process-line grid
(parse-line l)))
(count-lights grid))))
最佳答案
Java 原始数组对我来说已经足够了(在便宜的 4 岁笔记本电脑上半秒)。我没有费心拆箱索引。
(set! *unchecked-math* true)
(defn turn-off [^ints grid [r1 c1 r2 c2]]
(doseq [i (range r1 (inc r2))
k (range (+ c1 (* i 1000)) (+ c2 (* i 1000) 1))]
(aset grid k 0)))
(defn turn-on [^ints grid [r1 c1 r2 c2]]
(doseq [i (range r1 (inc r2))
k (range (+ c1 (* i 1000)) (+ c2 (* i 1000) 1))]
(aset grid k 1)))
(defn toggle [^ints grid [r1 c1 r2 c2]]
(doseq [i (range r1 (inc r2))
k (range (+ c1 (* i 1000)) (+ c2 (* i 1000) 1))]
(aset grid k (- 1 (aget grid k)))))
(defn count-on [^ints grid]
(areduce grid i cnt 0 (+ cnt (aget grid i))))
(defn day06a []
(let [grid (int-array (* 1000 1000))] ; 0-initialized via Java
(with-open [rdr (clojure.java.io/reader "input/input06.txt")]
(doseq [cmd (line-seq rdr)]
(let [v (map #(Integer/parseInt %) (re-seq #"[0-9]+" cmd))]
(cond (.startsWith cmd "turn off") (turn-off grid v)
(.startsWith cmd "turn on") (turn-on grid v)
(.startsWith cmd "toggle") (toggle grid v)))))
(count-on grid)))
关于scala - 为什么这个 Clojure 程序处理可变数组的速度如此之慢?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34153369/
为什么禁用类型像 type t = A of int | B of string * mutable int 虽然允许此类类型: type t = A of int | B of string * i
我正在寻找一种类似结构的数据结构,我可以从中创建多个实例并具有某种类型提示而不是不可变的。 所以我有这样的东西: class ConnectionConfig(NamedTuple): nam
我需要转到引用的结构: class SearchKnot { var isWord : Bool = false var text : String = "" var to
如sec 10.4.3中所述 当控制进入执行时,执行以下步骤 功能对象F(调用者)中包含的功能代码的上下文 提供thisArg,而调用方提供argumentsList: 如
i make a game that start display Activity indicator And activity indicator bottom display UiLable wi
编辑:我在这里不断获得支持。只是为了记录,我认为这不再重要。自从我发布它以来我就不再需要它了。 我想在 Scala 中执行以下操作... def save(srcPath: String, destP
使用可变对象作为 Hashmap 键是一种不好的做法吗?当您尝试使用已修改足以更改其哈希码的键从 HashMap 中检索值时,会发生什么? 例如,给定 class Key { int a; /
如果您在Kotlin中访问List类型的Java值,则将获得(Mutable)List!类型。 例如。: Java代码: public class Example { public stati
我编写了 str 类(内置)的以下扩展,以便执行以下操作:假设我有字符串 "Ciao" ,通过做"Ciao" - "a"我想要的结果是字符串 "Cio" 。这是执行此操作的代码,并且运行良好: cla
使用可变对象作为 Hashmap 键是一种不好的做法吗?当您尝试使用已修改足以更改其哈希码的键从 HashMap 中检索值时,会发生什么? 例如,给定 class Key { int a; /
我正在为我的公司设计一个数据库来管理商业贷款。每笔贷款都可以有担保人,可以是个人或公司,在借款业务失败时作为财务支持。 我有 3 个表:Loan、Person 和 Company,它们存储明显的信息。
我使用二进制序列化从 C# 类中保存 F# 记录。一切正常: F#: type GameState = { LevelStatus : LevelStatus
import javax.swing.JOptionPane; public class HW { public static void main(String[] args) { Strin
使用 flatbuffer mutable 有多少性能损失? 是否“正确”使用 FlatBuffers 来拥有一个应该可编辑的对象/结构(即游戏状态) 在我的示例中,我现在有以下类: class Ga
std::function create_function (args...) { int x = initial_value (args...); return [x] () mut
我需要在 for 循环中找到用户输入的字符。我通常会这样做 如果(句子[i] == 'e') 但是因为在这里,'e' 将是一个单字母字符变量,我不知道如何获取要比较的值。我不能只输入 if (sent
我有一个这样的算法: let seed: Foo = ... let mut stack: Vec = Vec::new(); stack.push(&seed); while let Some(ne
这个问题可能看起来非常基础,但我很难弄清楚如何做。我有一个整数,我需要使用 for 循环来循环整数次。 首先,我尝试了—— fn main() { let number = 10; // An
如果我有以下结构: struct MyStruct { tuple: (i32, i32) }; 以及以下函数: // This will not compile fn function(&mut s
我希望在每个 session 的基础上指定列的默认值。下面的脚本不起作用,但描述了我想如何使用它。我目前使用的是 MySQL 5.5.28,但如果需要可以升级。 CREATE TABLE my_tbl
我是一名优秀的程序员,十分优秀!