双向循环链表的基本操作.doc

双向循环链表的基本操作 #includeiostream using namespace std; struct DblNode { int data; DblNode *rLink; DblNode*lLink; }; class DblList { public: DblList(); ~DblList(); bool IsEmpty(); int GetLength(); void Output(); void ClearList(); bool HeadInsert(int e); bool TailInsert(int e); bool Insert(int pos,int e); int Locate(int e); bool DeleteNode(int pos,inte); bool Insert(int i,const int x,int d); bool SetData(int pos,int e); DblNode *GetNode(int pos); void Meun(); private: DblNode *first; DblNode *last; int Length; }; #includeDblList.h DblList::DblList() { first=new DblNode; if(!first) { exit(-1); } first-rLink=first; first-lLink=first; last=first; Length=0; } DblList::~DblList() { DblNode *p1=first; DblNode *p2; while(p1!=last) { p2=p1; p1=p1-rLink; delete p2; } delete last; } bool DblList::IsEmpty() { if(Length==0) return true; return false; } bool DblList::HeadInsert(int e) { DblNode *p=new DblNode; if(!p) return false; p-data=e; p-rLink=NULL; p-lLink=NULL; if(Length==0) { p-rLink=first; p-lLink=first; first-rLink=p; first-lLink=p; last=p; } else { p-rLink=first-rLink; p-lLink=first; first-rLink-lLink=p; first-rLink=p; } Length++; return true; } bool DblList::TailInsert(int e) { DblNode *p=new DblNode; if(!p) return false; p-data=e; p-rLink=NULL; p-lLink=NULL; last-rLink=p; p-lLink=last; last=p; last-rLink=first; first-lLink=last; Length++; return true; } bool DblList::Insert(int pos,int e) { if(pos=1) { return HeadInsert(e); } else if(posLength) { return TailInsert(e); } else { DblNode*p1=GetNode(pos-1); DblNode*p2=GetNode(pos); DblNode*p=new DblNode; if(!p)return false; p-data=e; p-rLink=p2; p-lLink=p1; p2-lLink=p; p1-rLink=p; Length++; return true; } } bool DblList::DeleteNode(int pos,inte) { if(pos1||posLength)return false; DblNode*p1=GetNode(pos-1); DblNode*p2=GetNode(pos); if(p2==last) { delete p2