回答編集履歴
3
対案を提示
test
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@@ -65,3 +65,73 @@
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http://docs.oracle.com/javase/jp/7/api/java/util/Collections.html#reverse(java.util.List)
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## 対案 : ソートを1回だけ実行する
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swordone様のご指摘を受け、ソート処理を1回で済ませるプログラムを以下に示します。
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`Collections.reverseOrder()`メソッドを使用しております。
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```java
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import java.util.ArrayList;
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import java.util.Collections;
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import java.util.Comparator;
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import java.util.List;
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public class Main {
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public static void main(String[] args) {
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List<String> devicesList = new ArrayList<String>();
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devicesList.add("SmartPhone");
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devicesList.add("Tablet");
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devicesList.add("MobilePhone");
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devicesList.add("Notebook");
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System.out.println(devicesList);
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Comparator<String> reverseOrder = Collections.reverseOrder();
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Collections.sort(devicesList, reverseOrder);
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System.out.println(devicesList);
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}
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}
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```
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実行結果
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```
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[SmartPhone, Tablet, MobilePhone, Notebook]
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[Tablet, SmartPhone, Notebook, MobilePhone]
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```
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http://docs.oracle.com/javase/jp/7/api/java/util/Collections.html#reverseOrder(java.util.Comparator)
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2
文言を修正
test
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@@ -1,4 +1,4 @@
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1
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-
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`Collections.reverse()`メソッドを使用すれば、`Comparator`クラスを実装しなくても実現できます。
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2
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3
3
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```java
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1
リンクを追記
test
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@@ -61,3 +61,7 @@
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[Tablet, SmartPhone, Notebook, MobilePhone]
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```
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http://docs.oracle.com/javase/jp/7/api/java/util/Collections.html#reverse(java.util.List)
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