#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#define LEN sizeof(struct Student)
struct Student
{
long num;
float score;
struct Student*next;
};
int n;
int main()
{
//Function declaration
struct Student* create();// For creating dynamic linked lists Function declaration , the function type is student Struct type, returns a header pointer
struct Student* del(struct Student* ,long);// Deletes a node at the specified location Function declaration, Parameter: chain header node + Delete node location + Return header pointer
struct Student* insert(struct Student*,struct Student*);// Insert a Student Type data Function declaration
void print(struct Student*);// Output the data in the linked list Function declaration , the parameter is the header pointer of the linked list
//Define variables
struct Student *head,*stu;//Defines a header pointer to a dynamic linked list with a new node
long del_num;
//Establish a linked list operation
printf("Input records:n");
head = create();//Creates a linked list and returns a header pointer
print(head);//Output all nodes
//Delete node operation
printf("nInput the deleted number:");
scanf("%ld",&del_num);
while(del_num!=0)//The loop ends when the student number is 0
{
head = del(head,del_num);//Returns the header address of the list after the node is deleted
print(head);//Output all nodes
printf("Input the deleted number:");
scanf("%ld",&del_num);
}
//Insert node operation
printf("nInput the inserted number:");
stu=(struct Student*)malloc(LEN);//Every time a node is inserted, a new node needs to be created
scanf("%ld %f",&stu->num,&stu->score);
while(stu->num!=0)//The loop ends when the student number entered is 0
{
head = insert(head,stu);//Returns the header address of the linked list
print(head);
printf("nInput the inserted number:");
stu = (struct Student*)malloc(LEN);
scanf("%ld %f",&stu->num,&stu->score);
}
return 0;
}
//A function that creates a linked list
struct Student* create()
{
struct Student *head;
struct Student *p1,*p2;
n=0;
p1=p2=(struct Student *)malloc(LEN);
scanf("%ld %f",&p1->num,&p1->score);
head=NULL;
while(p1->num!=0)
{
n++;
if(n==1)head=p1;
else p2->next=p1;//When first executed, this step is to point the header pointer to itself, and when n starts at 2, this step is used to point p2 to the next element
p2=p1;//Point p2 and p1 to the same storage area
p1=(struct Student*)malloc(LEN);//Open up dynamic storage and force a pointer of type struct Student to be returned
scanf("%ld %f",&p1->num,&p1->score);
}
p2->next=NULL;
return (head);
}
//Delete node function
struct Student* del(struct Student* head,long num)
{
struct Student *p1,*p2;
if(head==NULL)
{
printf("List null!n");
return (head);
}
p1=head;
while(num!=p1->num && p1->next!=NULL)
{
p2=p1;
p1=p1->next;
}
if(num==p1->num)
{
if(p1==head)
{
head=p1->next;
}
else
{
p2->next=p1->next;
}
printf("Delete:%ldn",num);
n=n-1;
}
else
{
printf("%ld not been found!",num);
}
return (head);
}
//The function that inserts a node
struct Student* insert(struct Student* head,struct Student * stud)
{
struct Student *p0,*p1,*p2;
p1=head;
p0=stud;
if(head==NULL)//The original linked list was an empty table
{
head=p0;p0->next=NULL;//Empty table when the inserted node as the header node
}
else//If it is not an empty table, it iterates to find the appropriate insertion location
{
while((p0->num>p1->num)&&(p1->next!=NULL))//Insert in student number order. If the number of student number inserted is large, it should be pushed backward
{
p2=p1;
p1=p1->next;//Move backward
}
}
if(p0->num<=p1->num)//I'm going to find the insertion position, and the insertion position is before the position that p1 is pointing to, which is the position that p2 is pointing to
{
if(head==p1)head=p0;//If the insertion position is before the head position, make the head point to p0
else p2->next=p0;//If not before the header position, make the next pointer to p2 point to the inserted data address, or p0
p0->next=p1;//Make the next pointer of p0 point to p1 to complete the data addition
}
else//Insert the student number in the last position
{
p1->next=p0;
p0->next=NULL;
}
n=n+1;//Number of records plus one
return(head);
}
//A function that outputs a linked list
void print(struct Student * head)
{
struct Student * p;
printf("Now,These %d records are:n",n);
p=head;
if(head!=NULL)
do
{
printf("%ld %5.1fn",p->num,p->score);
p=p->next;
}while(p!=NULL);
}