22 lines
653 B
Java
22 lines
653 B
Java
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.List;
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public class ArrayReverse {
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// ArrayList 反转元素
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// 双指针解法
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// 出自 java.util.Collections#reverse
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public static void main(String[] args) {
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List<Integer> list = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7));
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int size = list.size();
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Integer x, y;
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for (int begin = 0, mid = size >> 1, end = size - 1; begin < mid; begin++, end--) {
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x = list.get(begin);
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y = list.get(end);
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list.set(begin, y);
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list.set(end, x);
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}
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System.out.println(list);
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}
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}
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