38 lines
1.2 KiB
Java
38 lines
1.2 KiB
Java
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package chapter_stack_and_queue;
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import java.util.*;
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public class deque {
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public static void main(String[] args) {
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/* 初始化队列 */
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Deque<Integer> deque = new LinkedList<>();
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/* 元素入队 */
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deque.offerLast(2);
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deque.offerLast(5);
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deque.offerLast(4);
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deque.offerFirst(3);
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deque.offerFirst(1);
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System.out.println("队列 deque = " + deque);
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/* 访问队首元素 */
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int peekFirst = deque.peekFirst();
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System.out.println("队首元素 peekFirst = " + peekFirst);
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int peekLast = deque.peekLast();
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System.out.println("队尾元素 peekLast = " + peekLast);
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/* 元素出队 */
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int pollFirst = deque.pollFirst();
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System.out.println("队首出队元素 pollFirst = " + pollFirst + "，队首出队后 deque = " + deque);
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int pollLast = deque.pollLast();
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System.out.println("队尾出队元素 pollLast = " + pollLast + "，队尾出队后 deque = " + deque);
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/* 获取队列的长度 */
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int size = deque.size();
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System.out.println("队列长度 size = " + size);
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/* 判断队列是否为空 */
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boolean isEmpty = deque.isEmpty();
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}
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}
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