Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Competitive Programming in Ruby (101)
Search
yhara
September 10, 2016
Programming
0
730
Competitive Programming in Ruby (101)
yhara
September 10, 2016
Tweet
Share
More Decks by yhara
See All by yhara
静的型付けプログラミング言語Shiika
yhara
0
19k
それは残像だ
yhara
4
4.4k
スモートーク
yhara
0
2.9k
Ovto: Frontend web framework for Rubyists
yhara
0
7.5k
Ruby, Opal and WebAssembly
yhara
2
2.5k
Rubyで競技プログラミング(入門編)
yhara
0
1.9k
良いデバッグログはプロジェクトの資産である
yhara
54
18k
Let's make a functional language!
yhara
0
6.4k
Recent Updates (近況報告)
yhara
0
630
Other Decks in Programming
See All in Programming
ワンバイナリWebサービスのススメ
mackee
10
7k
人には人それぞれのサービス層がある
shimabox
3
420
抽象データ型について学んだ
ryounasso
0
200
クラシルリワードにおける iOSアプリ開発の取り組み
funzin
1
760
TypeScript だけを書いて Tauri でデスクトップアプリを作ろう / Tauri with only TypeScript
tris5572
2
490
CRUD から CQRS へ ~ 分離が可能にする柔軟性
tkawae
0
220
AIエージェントによるテストフレームワーク Arbigent
takahirom
0
230
TypeScript製IaCツールのAWS CDKが様々な言語で実装できる理由 ~他言語変換の仕組み~ / cdk-language-transformation
gotok365
6
350
ビカム・ア・コパイロット
ymd65536
1
190
JSAI2025 RecSysChallenge2024 優勝報告
unonao
1
340
"使いづらい" をリバースエンジニアリングする UI の読み解き方
rebase_engineering
0
100
テスト分析入門/Test Analysis Tutorial
goyoki
10
2.6k
Featured
See All Featured
Rails Girls Zürich Keynote
gr2m
94
13k
Why Our Code Smells
bkeepers
PRO
336
57k
"I'm Feeling Lucky" - Building Great Search Experiences for Today's Users (#IAC19)
danielanewman
228
22k
Learning to Love Humans: Emotional Interface Design
aarron
273
40k
10 Git Anti Patterns You Should be Aware of
lemiorhan
PRO
656
60k
The Power of CSS Pseudo Elements
geoffreycrofte
76
5.8k
The Myth of the Modular Monolith - Day 2 Keynote - Rails World 2024
eileencodes
25
2.8k
The Straight Up "How To Draw Better" Workshop
denniskardys
233
140k
Java REST API Framework Comparison - PWX 2021
mraible
31
8.6k
Intergalactic Javascript Robots from Outer Space
tanoku
271
27k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
14
1.5k
Automating Front-end Workflow
addyosmani
1370
200k
Transcript
Compe&&ve Programming in Ruby (101) RubyKaigi 2016 Kyoto A1er Party
LT (2016-09-10) @yhara (Yutaka Hara) RubyKaigi 2016 Kyoto LT (2016-09-10) 1
RubyKaigi 2016 Kyoto LT (2016-09-10) 2
Recently I'm trying Compe22ve Programming with my colleagues RubyKaigi 2016
Kyoto LT (2016-09-10) 3
Compe&&ve Programming RubyKaigi 2016 Kyoto LT (2016-09-10) 4
Programming contest RubyKaigi 2016 Kyoto LT (2016-09-10) 5
Write a program fast and correctly RubyKaigi 2016 Kyoto LT
(2016-09-10) 6
Need C(++, #) or Java? RubyKaigi 2016 Kyoto LT (2016-09-10)
7
You can use Ruby too! RubyKaigi 2016 Kyoto LT (2016-09-10)
8
Sites which supports Ruby • Sphere Online Judge • Aizu
Online Judge • yukicoder • AtCoder ←Today's topic RubyKaigi 2016 Kyoto LT (2016-09-10) 9
atcoder.jp • AtCoder Grand Contest • AtCoder Regular Contest •
AtCoder Beginner Contest • AtCoder Typical Contest RubyKaigi 2016 Kyoto LT (2016-09-10) 10
Don't join the contest RubyKaigi 2016 Kyoto LT (2016-09-10) 11
Try previous contests first ! RubyKaigi 2016 Kyoto LT (2016-09-10)
12
! • Any%me • No %me limit RubyKaigi 2016 Kyoto
LT (2016-09-10) 13
• AtCoder Grand Contest • AtCoder Regular Contest • AtCoder
Beginner Contest • AtCoder Typical Contest RubyKaigi 2016 Kyoto LT (2016-09-10) 14
AtCoder Beginner Contest • A: Very easy • B: Easy
• C: Easy? • D: Not really easy RubyKaigi 2016 Kyoto LT (2016-09-10) 15
But Ruby is slow...? ! RubyKaigi 2016 Kyoto LT (2016-09-10)
16
No problem! RubyKaigi 2016 Kyoto LT (2016-09-10) 17
Algorithm Ma-ers ! RubyKaigi 2016 Kyoto LT (2016-09-10) 18
Example: one-line Reversi RubyKaigi 2016 Kyoto LT (2016-09-10) 19
one-line Reversi • Given N pieces, flip Q ranges •
Calculate the final state ••••••••• 1..4 2..6 8..9 ɹɹ↓ ◦•••◦◦•◦◦ RubyKaigi 2016 Kyoto LT (2016-09-10) 20
Just flipping each pieces? ranges.each do |r| r.each do |i|
line[i] = !line[i] end end RubyKaigi 2016 Kyoto LT (2016-09-10) 21
RubyKaigi 2016 Kyoto LT (2016-09-10) 22
200,000 pieces ! 200,000 ranges ! RubyKaigi 2016 Kyoto LT
(2016-09-10) 23
Billions of flips ! ranges.each do |r| # <- 200,000
times r.each do |i| # <- 50,000 times or so line[i] = !line[i] end end RubyKaigi 2016 Kyoto LT (2016-09-10) 24
⏰ Time Limit = 2 sec. RubyKaigi 2016 Kyoto LT
(2016-09-10) 25
Be#er algorithm Memorize where color changes 10001 23005 ɹɹɹɹ↓ɹɹ↓ •••...•◦...◦•••
RubyKaigi 2016 Kyoto LT (2016-09-10) 26
Passed! ! RubyKaigi 2016 Kyoto LT (2016-09-10) 27
You can try Compe//ve Prograaming in Ruby ! (at least
for beginner contest) RubyKaigi 2016 Kyoto LT (2016-09-10) 28
! BTW ! RubyKaigi 2016 Kyoto LT (2016-09-10) 29
RubyKaigi 2016 Kyoto LT (2016-09-10) 30
ABC037-D • I couldn't pass with Ruby ! • Traversing
1000x1000 maze • Maybe with Ruby3...? RubyKaigi 2016 Kyoto LT (2016-09-10) 31
Crystal passes ※CrystalɿRuby-like sta0cally typed language RubyKaigi 2016 Kyoto LT
(2016-09-10) 32
Pypy2 passes ※Pypy2ɿFaster Python implemanta2on RubyKaigi 2016 Kyoto LT (2016-09-10)
33
Python3 passes!? ! RubyKaigi 2016 Kyoto LT (2016-09-10) 34
RubyKaigi 2016 Kyoto LT (2016-09-10) 35
RubyKaigi 2016 Kyoto LT (2016-09-10) 36
RubyKaigi 2016 Kyoto LT (2016-09-10) 37
(DON'T TRY THIS AT HOME !) RubyKaigi 2016 Kyoto LT
(2016-09-10) 38