December 2016
Intermediate to advanced
440 pages
9h 44m
Japanese
Content preview from アルゴリズムクイックリファレンス 第2版
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■
57
4
章
整列アルゴリズム
情報が前もってきちんと整列されていれば、多くの計算や作業が簡単になる。効
率的な整列アルゴリズムの探究は、コンピュータサイエンスの初期に盛んに行われ
た。実際、アルゴリズムの初期の研究の多くは、当時のコンピュータではメモリに
入りきらない大量のデータをどのように整列するかを扱っていた。最近のマシンは、
50
年前と比べて信じられないほど、高速かつ強力になっていて、今では一度にテラ
バイトのデータを処理できる。それほどまで大量のデータセットの整列は要求され
ないだろうが、多数のデータを整列する必要はよくあるだろう。本章では、最も重
要な整列アルゴリズムを取り上げ、ベンチマーク結果を示して、状況に応じて最良
の整列アルゴリズムを選択できるようにした。
4.0.1
用語
比較可能な要素の集まり（
collection
）
A
を整列対象とする。集まりの第
i
番目の
要素を
A[i ]
または
a
i
と表記する。先頭の要素は、
A[0]
と書く。
A[low, low
＋
n)
と
表記した場合は
n
個の要素
A[low ]
…
A[low
＋
n
−
1]
からなる部分集まりを指し、
A[low, low
＋
n ]
は、
n
＋
1
個の要素
A[low ]
…
A[low
＋
n ]
からなる部分集まりを指
す。
ある集まり
A
を整列（ソート）するとは、
A
の要素を、
A[i ]
＜
A[ j ]
ならば
i
＜
j
で
あるという性質を満たすように並べ替えることである。重複要素は連続していなけ
ればならない。すなわち、
A[i ]
＝
A[ j ]
ならば、
i
＜
k
＜
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.