operate.h

一个B-树实现与编辑

Status Operate(int j)
{
	int flag,x;
	Result V;
	if(j==0)
	{
		cout<<"退出本系统"<<endl;
		return OK;
	}
	else
	{
		cout<<"输入书号：";
	    cin>>x;cout<<endl;
	
	V=SearchBTree(T,x);
	
	switch(j){
case 1:
	
	cout<<"新书入库"<<endl;
	if(V.tag==1)
	{
		V.pt->recptr[V.i]->total+=A;
		V.pt->recptr[V.i]->now+=A;
	}
	else
	{
		Record *r;
	　　r=new Record;
	　　r->num=x;
	    r->now=A;
	  　r->total=A;
	   
        r->next=NULL;
	
	
		InsertBTree(T,x,r,V.pt,V.i);
	}
	
	    
	
	Print(T,40);
	
	break;
case 2:
	cout<<"清书出库"<<endl;
	if(V.tag==0)
	{
		cout<<endl<<"=========================================================================="<<endl<<endl;
		cout<<"书库没有这种书，请再次选择操作"<<endl;
		
	}
	else
		DeleteBTree(T,x,V.pt->recptr[V.i],V.pt,V.i);

	Print(T,40);
	break;
case 3:
	if(V.tag==1)
	{
		if(V.pt->recptr[V.i]->now>0)
	{
		
		Lender *L1,*L2;
		L1=new Lender;
		L1->next=NULL;
		cout<<"借者书证号:";
		cin>>L1->card;cout<<endl;
		cout<<"归还日期:";
		cin>>L1->time;cout<<endl; 
		if(V.pt->recptr[V.i]->next==NULL)
           V.pt->recptr[V.i]->next=L1;
		else
		{
			L2=V.pt->recptr[V.i]->next;
			while(L2->next!=NULL)
				L2=L2->next;
			L2->next=L1;
		}
		cout<<"借出"<<x<<"号书一本"<<endl<<endl;
		V.pt->recptr[V.i]->now-=1;
	}
	else 
		cout<<"此种书已借完"<<endl<<endl;
	}
	else
		cout<<"没有这种书"<<endl<<endl;
	break;
case 4:
	if(V.tag==1&&V.pt->recptr[V.i]->now<V.pt->recptr[V.i]->total)
	{
		
		
		Lender *L1,*L2;
		char cards[20];
		L1=V.pt->recptr[V.i]->next;
		cout<<"还书者书证号：";
		cin>>cards;
		cout<<endl;
		while(L1!=NULL)
		{
			L2=L1;
			if(!strcmp(L1->card,cards))
			{
				L2->next=L1->next;
				cout<<"还"<<x<<"号书一本"<<endl;
				V.pt->recptr[V.i]->now+=1;
				break;
				
				}
			else
			
				L1=L1->next;
				
		}
		if(L1==NULL)cout<<"输入有误"<<endl<<endl;//书证号与所借的书不匹配
	}
	else
		cout<<"输入有错"<<endl<<endl;        //书库中不存在此类书
	break;

	
default:break;
	}
	cout<<endl<<"=========================================================================="<<endl<<endl;
	cout<<"请选择下一步操作"<<endl<<endl;
	cout<<"flag:";
		cin>>flag;
		cout<<endl;
	
	
		Operate(flag);return OK;
	
	}
	
}