🗂️ 数据结构：数据怎么摆🗂️ Data Structure: How Data Is Laid Out

上一片，小电脑把榨汁步骤打包成了函数。可生意越来越好：盘子、顾客、文件，堆成了山。乱放就难找。这一片，学会给数据摆好位置。 Last leaf, the little computer packed its juice steps into a function. But business is booming: plates, customers and files pile up. Messy piles are hard to search. This leaf teaches how to give data a proper place.

第 1 步：一摞盘子——栈Step 1: A pile of plates — the stack

数据一多，怎么摆才好拿？With lots of data, how should it be laid out?

栈：一摞盘子，后进先出 — 先认识数据结构：数据的摆放方式。最简单的是数组：一排编号格子。栈像一摞盘子。新盘子放顶上，取也先取顶上。这叫后进先出。撤销键就是栈：最后一步最先撤。 Meet the data structure: a way to lay data out. The simplest is the array: a row of numbered slots. A stack is a pile of plates. New plates go on top, and the top comes off first. That is last in, first out. Undo is a stack: the last step is undone first.

可顾客排队时，能让最后来的先拿吗？But in a line of customers, should the last one go first?

第 2 步：排好队——队列Step 2: Waiting in line — the queue

队列：排队买果汁，先到先得 — 不行，那得用队列。队列就像排队买果汁。从队尾加入，从队头离开。先到先得，也叫先进先出。打印机排任务，游戏排房间，都靠队列。 No — that needs a queue. A queue is a line for juice. Join at the back, leave from the front. First come, first served: first in, first out. Printer jobs and game matchmaking both wait in queues.

数据分了上下级，一排排放不下，怎么办？What if data has levels that rows can’t hold?

第 3 步：分层放——树Step 3: Levels — the tree

树：文件夹一层层分下去 — 用树！一个根文件夹，分出子文件夹，再分出文件。你电脑里的文件夹，就是一棵树。顺着树枝往下找，几步就到。网页、家谱、目录，也都是树。 Use a tree! One root folder splits into sub-folders, then into files. The folders on your computer form a tree. Follow the branches down and you arrive in a few steps. Web pages, family trees and contents pages are trees too.

🎮 你来摆订单（30 秒）🎮 Your turn: store the orders (30 seconds)

道理讲完了。再添一位字典：报名字直接翻到。先把 4 张订单放进四种结构，再接 4 关：给场景挑结构。Theory done. Meet one more: the dictionary, which jumps straight to a name. First put 4 orders into four structures, then take 4 rounds: pick the right structure for each scene.

一句话记住它：数据结构 = 数据的摆放方式；摆法决定谁先出来、找得多快。 Remember it in one line: a data structure = how data is laid out; the layout decides who comes out first and how fast you find things.

栈后进先出（盘子），队列先进先出（排队）Stack: last in, first out (plates); queue: first in, first out (a line) 数组按编号拿，字典按名字找，一步到位Array grabs by number, dictionary finds by name — one step 树一层层分下去：文件夹就是树A tree splits level by level: folders are a tree

内容参考 OpenStax 等公开教材，多来源核对 · AI 生成、人工审核 · 发现错误欢迎指正，帮这片叶子长得更好。 Based on OpenStax and other open textbooks, cross-checked across sources · AI-generated, human-reviewed · Spotted a mistake? Tell us — help this leaf grow.