Sturcture.Heap 堆（最大堆實現(最小堆實現類似)）

最大堆實現(最小堆實現類似)

package Structure.Heap;
import java.util.Iterator;
import java.util.Vector;
/*Author: CPlusPlus小碼農
 *If any question, 
 *Please contact:           
 * http://daixiecplusplus.blog.163.com/
 * QQ:1926742804
 */
public class MaxHeap<E extends Comparable<E> >{
	private int maxSize_;
	private int length_;
	Object[] data_;
	public MaxHeap(int size_)
	{
		maxSize_ = size_;
		length_ = 0;
		data_ = new Object[maxSize_+1];
	}
	
	private void DoubleSize()
	{
		Object[] temp = new Object[2*maxSize_+1];
		for(int i = 1;i<= maxSize_;++i)
		{
			temp[i] = data_[i];
		}
		data_ = temp;
		maxSize_ *= 2;
	}
	
	public void BuildHeap(Vector<E> v)
	{
		Iterator<E> it = v.iterator();
		while(it.hasNext())
		{
			++length_;
			data_[length_] = it.next();
			if(length_ == maxSize_) DoubleSize();
		}
		
		int begin = length_ /2;
		for(;begin >= 1 ; --begin)
		{
			SiftDown(begin,length_);
		}
	}
	
	private void Swap(int i,int j)
	{
		Object temp = data_[i];
		data_[i] = data_[j];
		data_[j] =temp;
	}
	public void Sort()
	{
		for(int i = length_ ; i > 1;--i)
		{
			Swap(i,1);
			SiftDown(1,i-1);
		}
	}
	
	public void SiftDown(int j,int size)
	{
		int maxSon = 0;
		data_[0] = data_[j];
		for(;j * 2 <= size; j = maxSon)
		{
			maxSon = j * 2;
			if(maxSon != size)
			{
				if(((E)data_[maxSon+1]).compareTo((E)data_[maxSon]) > 0)
					maxSon++;
			}
			if(((E)data_[maxSon]).compareTo((E)data_[0]) > 0)
			{
				data_[j] = data_[maxSon];
			}
			else break;
		}
		data_[j] = data_[0];
		
	}
	
	public void Print()
	{
		for(int i = 1;i <= length_ ; ++i)
		{
			System.out.print(data_[i] + " ");
		}
		System.out.println();
	}
	
	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Vector<Integer> v = new Vector<Integer>();
		v.add(30);
		v.add(60);
		v.add(8);
		v.add(40);
		v.add(70);
		v.add(12);
		v.add(10);
		
		MaxHeap<Integer> mh = new MaxHeap<Integer>(10);
		mh.BuildHeap(v);
		mh.Print();
		System.out.println();
		
		mh.Sort();
		mh.Print();
	}

}