xt7-10-1.cpp
上传用户:liubin
上传日期:2022-06-13
资源大小:85k
文件大小:3k
- #include <iostream>
- using namespace std;
- #define NULL 0
- struct student
- {long num;
- float score;
- student *next;
- };
- int n;
- int main()
- { student *creat(void);
- student *del(student *,long);
- student *insert(student *,student *);
- void print(student *);
- student *head,stu;
- long del_num;
- cout<<"input records:"<<endl;
- head=creat(); //返回头指针
- print(head); //输出全部结点
- cout<<endl<<"input the deleted number:";
- cin>>del_num; //输入要删除的学号
- head=del(head,del_num); //删除后链表的头地址
- print(head); //输出全部结点
- cout<<endl<<"input the inserted record:"; //输入要插入的结点
- cin>>stu.num>>stu.score;
- head=insert(head,&stu); //返回地址
- print(head); //输出全部结点
- cout<<endl<<"input the inserted record:"; //输入要插入的结点
- cin>>stu.num>>stu.score;
- head=insert(head,&stu); //返回地址
- print(head);
- return 0;
- }
- student *creat(void) //建立链表的函数
- {student *head;
- student *p1,*p2;
- n=0;
- p1=p2=new student; //开辟一个新单元,并使p1,p2指向它
- cin>>p1->num>>p1->score;
- head=NULL;
- while(p1->num!=0)
- {n=n+1;
- if(n==1) head=p1;
- else p2->next=p1;
- p2=p1;
- p1=new student;
- cin>>p1->num>>p1->score;
- }
- p2->next=NULL;
- return(head);
- }
- student *del(student *head,long num) //删除结的函数
- {student *p1,*p2;
- if (head==NULL) //是空表
- {cout<<"list null!"<<endl; return(head);}
- p1=head; //使p1指向第一个结点
- while(num!=p1->num && p1->next!=NULL) //p1指向的不是所要找的结点且后面还有结点
- {p2=p1; p1=p1->next;} //p1后移一个结点
- if(num==p1->num) //找到了
- {if(p1==head) head=p1->next; //若p1指向的是首结点,把第二个结点地址赋予head
- else p2->next=p1->next; //否则将下一结点地址赋给前一结点地址
- cout<<"delete:"<<num<<endl;
- n=n-1;
- }
- else cout<<"cannot find "<<num; //找不到该结点
- return(head);
- }
-
- student *insert(student *head,student *stud) //插入结点的函数
- {student *p0,*p1,*p2;
- p1=head; //使p1指向第一个结点
- p0=stud; //指向要插入的结点
- if(head==NULL) //原来的链表是空表
- {head=p0;p0->next=NULL;} //使p0指向的结点作为头结点
- else
- {while((p0->num>p1->num) && (p1->next!=NULL))
- {p2=p1; //使p2指向刚才p1指向的结点
- p1=p1->next;} //p1后移一个结点
- if(p0->num<=p1->num)
- {if(head==p1) head=p0; //插到原来第一个结点之前
- else p2->next=p0; //插到p2指向的结点之后*/
- p0->next=p1;}
- else
- {p1->next=p0; p0->next=NULL;}} //插到最后的结点之后
- n=n+1; //结点数加1
- return (head);
- }
-
- void print(student *head) //输出链表的函数
- {student *p;
- cout<<"Now,These "<<n<<" records are:"<<endl;
- p=head;
- if(head!=NULL)
- do
- {cout<<p->num<<" "<<p->score<<endl;
- p=p->next;
- }while(p!=NULL);
- }