第一章课后习题1.14

1.14 设计一个泛型类orderedCollection,它存储的Comparable对象的集合(在数组中),以及该集合的当前大小。

提供public方法isEmpty,makeEmpty,insert,remove,findMin和findMax。finfMin和findMax分别返回该集合中最小的和最大T对象的引用(如果该集合为空,则返回null)

package com.algorithm.chapterone;

/**
 * 设计一个泛型类orderedCollection,它存储的Comparable对象的集合(在数组中),以及该集合的当前大小。
 * 提供public方法isEmpty,makeEmpty,insert,remove,findMin和findMax。finfMin和findMax分别返回该集合中最小的和最大T对象的引用(如果该集合为空,则返回null)
 * @author Gao·Rongzheng
 *
 */
public class OrderCollection<E> {
    private static final Comparable[] EMPTY_ELEMENTDATA = {};
    private Comparable[] elementData;
    private int size;
    
    public OrderCollection() {
        elementData = EMPTY_ELEMENTDATA;
    }
    
    public Comparable[] getElement() {
        return elementData;
    }

    public void setElement(Comparable[] elementData) {
        this.elementData = elementData;
        size = elementData.length;
    }
    
    public int getSize() {
        return size;
    }
    
    public boolean isEmpty() {
        return size == 0;
    }

    public void makeEmpty() {
        elementData = EMPTY_ELEMENTDATA;
    }
    
    public void insert(E e) {
        Comparable[] temp = new Comparable[size + 1];
        System.arraycopy(elementData, 0, temp, 0, size);
        elementData = temp;
        size = elementData.length;
    }
    
    public void remove(E e) {
        Comparable[] temp = new Comparable[size - 1];
        for (int i = 0; i < size; i++) {
            if (elementData[i].equals(e)) {
                System.arraycopy(elementData, 0, temp, 0, i);
                System.arraycopy(elementData, i+1, temp, i, size-i-1);
                break;
            }
        }
        elementData = temp;
    }
    
    public void remove(int index) {
        Comparable[] temp = new Comparable[size - 1];
        for (int i = 0; i < size; i++) {
            if (i == index) {
                System.arraycopy(elementData, 0, temp, 0, i);
                System.arraycopy(elementData, i+1, temp, i, size-i-1);
                break;
            }
        }
        elementData = temp;
    }
    
    public Comparable findMin() {
        if (size == 0)
            return null;
        int min = 0;
        for (int i = 0; i < size; i++) {
            if (elementData[i].compareTo(elementData[min]) <= 0)
                min = i;                
        }
        return elementData[min];
    } 
    
    public Comparable findMax() {
        if (size == 0)
            return null;
        int max = 0;
        for (int i = 0; i < size; i++) {
            if (elementData[i].compareTo(elementData[max]) > 0)
                max = i;                
        }
        return elementData[max];
    }
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub

    }

}

 

posted @ 2019-08-29 14:25 从入门到入坟 阅读(...) 评论(...) 编辑 收藏