回答編集履歴
1
Collections\.fill
answer
CHANGED
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@@ -4,4 +4,20 @@
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4
4
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ArrayList<Integer> sample = new ArrayList<>(Collections.nCopies(7, 1));
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5
5
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System.out.println(sample.size() +" "+ sample);
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6
6
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//=> 7 [1, 1, 1, 1, 1, 1, 1]
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7
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-
```
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7
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+
```
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8
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+
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9
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+
もう一つ
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10
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+
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11
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+
```java
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12
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import java.util.*;
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13
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+
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14
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//ArrayList作成（ここは適当に）
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15
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ArrayList<Integer> sample = new ArrayList<>(Arrays.asList(new Integer[7]));
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16
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System.out.println(sample.size() +" "+ sample);
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17
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//=> 7 [null, null, null, null, null, null, null]
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18
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+
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19
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//1で埋める
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20
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Collections.fill(sample, 1);
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21
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System.out.println(sample.size() +" "+ sample);
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22
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//=> 7 [1, 1, 1, 1, 1, 1, 1]
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23
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```
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