數據結構複習(4)---隊列

上一章：數據結構複習(3)—棧

package cjy.datastructure;

import java.util.Arrays;

public class Queue {
	private int[] elements;

	public Queue() {
		elements = new int[0];
	}

	/**
	 * 入隊
	 * 
	 * @param element
	 */
	public void push(int element) {
		int[] array = new int[elements.length + 1];
		for (int i = 0; i < elements.length; i++) {
			array[i] = elements[i];
		}
		array[elements.length] = element;
		elements = array;
	}

	/**
	 * 出隊
	 */
	public int pop() {
		if (elements.length <= 0) {
			throw new RuntimeException("數組下標越界，隊列爲空");
		}
		int element = elements[0];
		int[] array = new int[elements.length - 1];
		for (int i = 0; i < array.length; i++) {
			array[i] = elements[i + 1];
		}
		elements = array;
		return element;
	}

	/**
	 * 判空
	 * 
	 * @return
	 */
	public boolean isEmpty() {
		return elements.length == 0;

	}

	/**
	 * 打印隊列元素
	 */
	public void show() {
		System.out.println(Arrays.toString(elements));
	}
}