链表就地倒转

                             一个链表就地倒转的函数。

 

链表倒转函数.   
    
  code*   inverse(code*   head)     //逆向输出   
  ...{   
                  code*   p1;   
                  code*   p2;   
    
                  if(head   &&   head->next)   //超过2个结点   
                  ...{   
                                  p1=head;   
                                  p2=head->next;   
                  }   
                  else   
                                  exit(1);   
    
                  while(p2!=NULL)     //head   记录头结点，p1记录将处理的前一个结点，p2记录处理的结点   
                  ...{   
                                  p1->next=p2->next;   
                                  p2->next=head;   
                                  head=p2;   
                                  p2=p1->next;   
                  }   
    
                  return   head;   
  }