回答編集履歴
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ちゃんと動くやーつ
test
CHANGED
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@@ -7,3 +7,51 @@
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```
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再帰使ってるのですぐスタックオーバーフローになっちゃいますが。
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### 追記
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すみません脳死で作ってたのでツリーが偏ります。まじめにやると。
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```JavaScript
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function build(xs){
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if(xs === undefined || !Array.isArray(xs) || xs.length === 0){
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return undefined
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} else if(xs.length === 1){
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return xs
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} else if(xs.length === 2){
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return xs
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} else {
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const i = Math.floor(xs.length / 2)
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const inits = xs.splice(0, i)
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const tails = xs.splice(i -i , xs.length)
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return [build(inits), build(tails)]
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}
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}
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ys = [...Array(10).keys()]
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console.log(build(ys))
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```
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こんな感じです。
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[動くコード](https://playcode.io/718556)
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