28 lines
656 B
Java
28 lines
656 B
Java
/**
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* Data Structures & Algorithms 6th Edition
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* Goodrich, Tamassia, Goldwasser
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* Code Fragment 6.9
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*
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* An implementation of the Queue interface
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* */
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/**
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*
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* @author Gabriel Venberg
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*/
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public interface Queue<E> {
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/** returns the number of elements in the queue*/
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int size();
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/** tests whether the queue is empty*/
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boolean isEmpty();
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/**inserts an element at the rear of the queue*/
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void enqueue(E e);
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/**returns, but does not remove, the first element of the queue (null if empty). */
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E first();
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/** removes and returns the first element of the queue (null if empty)*/
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E dequeue();
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}
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