linklist.java

是算术表达的计算

public class LinkList
{
	Node firstnode;	
	int length;
	public LinkList()
	{
		firstnode=null;
		length=0;
	}
	public LinkList(double da)
	{
		firstnode=new Node(da);
		length=1;
	}
	void insertinorder(double da)
	{
		if(firstnode==null)
		{
			firstnode=new Node(da);
			length++;
			return;
		}
		if(da<firstnode.getData ())
		{
			firstnode=new Node(da,firstnode);
			length++;
			return;
		}
		Node current=firstnode,beforecurrent=current;
		while(current!=null && current.getData()<=da)
		{
			beforecurrent=current;
			current=current.next;			
		}
		if(current==null)
		{
			beforecurrent.next=new Node(da);
		}
		else
		{
			beforecurrent.next=new Node(da,current);
		}
		length++;
	}
}