数据结构——多项式相加

  
    

   
     
   
     #include 
   
     <
   
     iostream
   
     >
   
     

   
     using
   
      
   
     namespace
   
      std;


   
     struct
   
      linkpolyn
{
 
   
     int
   
      coef;
 
   
     int
   
      expn;
 
   
     struct
   
      linkpolyn 
   
     *
   
      next;
};
typedef 
   
     struct
   
      linkpolyn LinkPolyn;


   
     //
   
     创建链表函数
   
     

   
     LinkPolyn 
   
     *
   
     Creat()
{
 LinkPolyn 
   
     *
   
     h,
   
     *
   
     p;
 h
   
     =
   
     (LinkPolyn 
   
     *
   
     ) malloc(
   
     sizeof
   
     (LinkPolyn));
 h
   
     ->
   
     next
   
     =
   
     NULL;
 LinkPolyn 
   
     *
   
     temp;
 temp
   
     =
   
     h;
 cout
   
     <<
   
     "
   
     请输入: 
   
     "
   
     <<
   
     endl;
 
   
     do
   
     
 {
 p
   
     =
   
     (LinkPolyn 
   
     *
   
     ) malloc(
   
     sizeof
   
     (LinkPolyn)); 
   
     //
   
     给第一个节点分配内存
   
     

   
      cin
   
     >>
   
     p
   
     ->
   
     coef
   
     >>
   
     p
   
     ->
   
     expn;
 
   
     if
   
     (p
   
     ->
   
     coef 
   
     ==
   
      
   
     0
   
      
   
     &&
   
      p
   
     ->
   
     expn
   
     ==
   
     0
   
     )
 
   
     break
   
     ;
 p
   
     ->
   
     next
   
     =
   
     temp
   
     ->
   
     next;
 temp
   
     ->
   
     next
   
     =
   
     p;
 temp
   
     =
   
     p;
 }
   
     while
   
     (
   
     1
   
     ); 
   
     //
   
     以0结束输入
   
     

   
      
   
     return
   
      h;
}
   
     //
   
     end creat


   
     //
   
     打印输出函数
   
     

   
     void
   
      PrintPolyn(LinkPolyn 
   
     *
   
     h)
{
 LinkPolyn 
   
     *
   
      p1;
 p1
   
     =
   
     h
   
     ->
   
     next;
 
   
     if
   
     (h
   
     ->
   
     next
   
     ==
   
     NULL)
 {
 cout
   
     <<
   
     "
   
     Polyn is empty!
   
     "
   
     <<
   
     endl;
 }
 
   
     else
   
     
 {
 
   
     while
   
     (p1
   
     !=
   
     NULL)
 {
 cout
   
     <<
   
     p1
   
     ->
   
     coef
   
     <<
   
     "
   
     x^
   
     "
   
     <<
   
     p1
   
     ->
   
     expn
   
     <<
   
     "
   
     +
   
     "
   
     ;
 p1
   
     =
   
     p1
   
     ->
   
     next;
 }
 cout
   
     <<
   
     "
   
     end
   
     "
   
     <<
   
     endl;
 }
}
   
     //
   
     end printPolyn



   
     //
   
     表达式相加
   
     

   
     LinkPolyn 
   
     *
   
      add_Polyn(LinkPolyn 
   
     *
   
      ha , LinkPolyn 
   
     *
   
      hb)
{
 LinkPolyn 
   
     *
   
      pa,
   
     *
   
      pb;
 pa
   
     =
   
     ha
   
     ->
   
     next;
 pb
   
     =
   
     hb
   
     ->
   
     next;
 LinkPolyn 
   
     *
   
      prea, 
   
     *
   
     preb;
 prea
   
     =
   
     ha;
 preb
   
     =
   
     hb;

 
   
     while
   
     (pa 
   
     &&
   
      pb)
 {
 
   
     if
   
     (pa
   
     ->
   
     expn 
   
     <
   
      pb
   
     ->
   
     expn)
 {
 prea
   
     =
   
     pa;
 pa
   
     =
   
     pa
   
     ->
   
     next; 
 }
 
   
     else
   
      
   
     if
   
     (pa
   
     ->
   
     expn 
   
     ==
   
      pb
   
     ->
   
     expn)
 {
 
   
     if
   
     (pa
   
     ->
   
     coef 
   
     +
   
      pb
   
     ->
   
     coef 
   
     !=
   
     0
   
     )
 {
 pa
   
     ->
   
     coef 
   
     +=
   
      pb
   
     ->
   
     coef;
 prea
   
     =
   
     pa;
 }
 
   
     else
   
     
 {
 prea
   
     ->
   
     next
   
     =
   
     pa
   
     ->
   
     next;
 }
 preb
   
     ->
   
     next
   
     =
   
     pb
   
     ->
   
     next;
 pa
   
     =
   
     pa
   
     ->
   
     next;
 pb
   
     =
   
     pb
   
     ->
   
     next;
 } 
 
   
     else
   
     
 {
 preb
   
     ->
   
     next
   
     =
   
     pb
   
     ->
   
     next;
 pb
   
     ->
   
     next
   
     =
   
     pa;
 prea
   
     ->
   
     next
   
     =
   
     pb;

 pb
   
     =
   
     preb
   
     ->
   
     next;
 prea
   
     =
   
     prea
   
     ->
   
     next;
 }
 }

 
   
     if
   
     (pb) 
   
     //
   
     讲多项式B中未完成的链接到A山去
   
     

   
      {
 prea
   
     ->
   
     next
   
     =
   
     pb;
 }
 
   
     return
   
      ha;
}


   
     int
   
      main()
{
 LinkPolyn 
   
     *
   
     head1;

 
   
     //
   
     创建多项式1
   
     

   
      head1
   
     =
   
     Creat(); 
   
     //
   
     head1接受返回的指向头结点指针
   
     

   
      PrintPolyn(head1);

 
   
     //
   
     创建多项式2
   
     

   
      LinkPolyn 
   
     *
   
     head2;
 head2
   
     =
   
     Creat(); 
   
     //
   
     head1接受返回的指向头结点指针
   
     

   
      PrintPolyn(head2);

 
   
     //
   
     多项式相加
   
     

   
      LinkPolyn 
   
     *
   
     head3;
 head3
   
     =
   
     add_Polyn(head1 , head2); 
   
     //
   
     指针要更新
   
     

   
      PrintPolyn(head3); 
   
     //
   
     输出相加后的表达式
   
     

   
      
   
     return
   
      
   
     0
   
     ;
}