📄 p85temp.cpp
字号:
#include <stdio.h>
enum Boolean { False, True };
template <class Type> class List; //链表类的前视定义
template <class Type> class ListIterator; //链表结点类的前视定义
template <class Type> class ListNode { //链表结点类的类声明
friend class List <Type>; //友元
friend class ListIterator <Type>; //友元
friend class Polynomial;
friend Polynomial operator + ( const Polynomial & ah, const Polynomial & bh );
public:
ListNode ( const Type value ) : data (value), link (NULL) { }
//………
private:
Type data;
ListNode<Type> *link;
};
template <class Type> class List { //链表类的类声明
public:
friend class ListIterator<Type>;
List ( const Type value) { last =first = new ListNode<Type> (value) ; } //构造函数
int sum ();
void Add ( const Type value ) ;
//………
private:
ListNode<Type> *first, *last;
};
template <class Type> class ListIterator { //链表游标类的类声明
public:
ListIterator ( const List<Type> & l ) : list (l), current (l.first) { }
Boolean NotNull ( );
Boolean NextNotNull ( );
ListNode<Type>* First ( );
ListNode<Type>* Next ( );
private:
const List<Type> & list; //引用一个已存在的链表
ListNode<Type> *current; //指向链表中的一个结点
}
template <class Type> Boolean ListIterator<Type>::NotNull ( ) {
//检查链表中当前元素是否非空
if ( current != NULL ) return True; //链表当前结点指针非空
else return False;
}
template <class Type> Boolean ListIterator<Type>::NextNotNull ( ) {
//检查链表中下一元素是否非空
if ( current != NULL && current->link != NULL ) return True;
else return False;
}
template <class Type> ListNode<Type>* ListIterator<Type>::First ( ) {
//返回指向链表中表头结点的指针
if ( list.first->link != NULL ) { current = list.first; }
else { current = NULL; }
return current ;
}
template <class Type> ListNode<Type>* ListIterator<Type>::Next ( ) {
//返回指向链表中下一个结点的指针
if ( current != NULL && current->link != NULL ) { current = current->link; }
else { current = NULL; }
return current;
}
char compare ( int a, int b ) {
if ( a > b ) return '>';
else if ( a == b ) return '=';
else return '<';
}
struct Term { //用链表表示的多项式中, 链表结点的定义
int coef; //系数
int exp; //指数
void Init ( int c, int e ) { coef = c; exp = e; }
};
class Polynomial { //多项式类的定义
friend Polynomial operator + ( const Polynomial &, const Polynomial & );
private:
List<Term> poly; //单链表结构, 数据部分是Term
};
Polynomial operator + ( const Polynomial & ah, const Polynomial & bh ) {
//两个带头结点的按降幂排列的多项式链表的头指针分别是ah和bh, 返回是结果多项式链表的表头指针,
//指向ah的表头结点, 且结果不另外占用存储, 覆盖ah和bh链表
ListNode<Term> *pa, *pb, *pc, *p;
ListIterator<Term> Aiter ( ah.poly );
ListIterator<Term> Biter ( bh.poly );
pa = pc = Aiter.First ( ); pb = Biter.First ( ); //取得ah与bh的表头结点
pa = Aiter.Next ( ); pb = Biter.Next ( ); //pa、pb是链表ah、bh的检测指针
delete pb; //保留ah的表头结点, 删去bh的表头结点
while ( Aiter.NotNull ( ) && Biter.NotNull ( ) ) //两两比较
switch ( compare ( pa->data.exp, pb->data.exp ) ) {
case '=' : //pa→exp==pb→exp
pa->data.coef = pa->data.coef+pb->data.coef; //系数相加
p = pb; pb = Biter.Next ( ); delete p; //删去原pb所指结点
if ( !pa->data.coef ) { p = pa; pa = Aiter.Next ( ); delete p; } //相加为零, 不要
else { pc->link = pa; pc = pa; pa = Aiter.Next ( ); } //相加不为零, 加入ch链
break;
case '<' : //pa→exp < pb→exp
pc->link = pb; pc = pb; pb = Biter.Next ( );
break;
case '>' : //pa→exp > pb→exp
pc->link = pa; pc = pa; pa = Aiter.Next ( );
}
if ( Aiter.NotNull ( ) ) pc->link = pa; //剩余部分链入ch链
else pc->link = pb;
return ah;
}
Polynomial operator * ( const Polynomial & ah, const Polynomial & bh )
void Calc ( ) {
Polynomial a, b, c, d, t;
cin >> a; cin >> b; cin >> c; //读入3个多项式
t = a * b; d = t + c;
cout << d;
}
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -