学生成绩排序及平均分计算利用c语言链表创建插入删除.doc

#include<stdio.h>
#include<malloc.h>
#define NULL 0
#define LEN sizeof(struct student)
struct student
{
long num;
float score;
struct student *next;
};
int n;
struct student *creat(void)//创建链表
{
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=n+1;
if(n==1)head=p1;
else p2->next=p1;
p2=p1;
p1=(struct student *)malloc(LEN);
scanf("%ld,%f",&p1->num,&p1->score);
}
p2->next=NULL;
return(head);//带回链表的头指针
}

void print(struct student *head)//输出链表
{
struct student *p;
printf("\nNow,there %d records are:\n",n);
p=head;
if(head!=NULL)
do
{
printf("%ld %5.1f\n",p->num,p->score);
p=p->next;
}
while(p!=NULL);
}

void averprintf(struct *head)//平均值输出
{
struct student *p;
float aver,sum=0,high=0,low=0;
long num1;

printf("\nNow,the averge score is:\n");
p=head;
if(head!=NULL)
do
{
sum=sum+p->score;
p=p->next;
}
while(p!=NULL);
aver=sum/n;printf("%5.1f\n",aver);}

void highprintf(struct student *p)/*求最高分*/

{
int high=p->score;
long num1=p->num;
do {if (high<p->score)
{high=p->score;
num1=p->num;}
p=p->next ;}while (p!=NULL);
printf("\nThe highest score is:%d,and its number is:%ld\n",high,num1);}

void lowprintf(struct student *p)/*求最低分*/

{
int low=p->score;
long num1=p->num;
do{if (low>p->score)
{low=p->score;
num1=p->num;}
p=p->next;}while (p!=NULL);
printf("\nThe lowest score is:%d,and its number is:%ld\n",low,num1);}

void sort(struct student *head)//学生成绩排序
{
struct student *p1,*p2;
float i;long t;
printf("Students from low to high ranking\n");
p1=head;
if(head==NULL)
{
printf("it is blank\n");
}
else
{
while(p1!=NULL)
{
p2=p1->next;
while(p2!=NULL)
{
if(p1->score>p2->score)
{
i=p2->score;
p2->score=p1->score;
p1->score=i;
t=p2->num;
p2->num=p1->num;
p1->num=p2->num;
}
p2=p2->next;
}
p1=p1->next;
}
}
while(p1!=0)
{
printf("%ld %5.1f\n",head->num,p1->score);
head->next;
}
}

struct student *del(struct student *head,long num)//删除节点
{struct student *p1,*p2;
if(head==NULL){printf("\nlist 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:%ld\n",num);
n=n-1;
}
else printf("%ld not been found!\n",num);return(head);
}

struct student *insert(struct student *head,struct student *stud)//插入节点
{ struct student *p0,*p1,*p2;
p1=head;
p0=stud;
if(head==NULL)
{head=p0;p0->next=NULL;}
else
{while((p0->num>p1->num)&&(p1->next!=NULL))
{p2=p1;p1=p1->next;}
if(p0->num<=p1->num)
{if(head==p1)head=p0;
else p2->next=p0;
p0->next=p1;}
else
{p1->next=p0;p0->next=NULL;}
}
n=n+1;
return(head);
}

void main()
{
struct student *head,*stu;
long del_num;
printf("input records:\n");
head=creat();
lowprintf(head);//加入排序，最高分，最低分调用函数
highprintf(head);
averprintf(head);

//删除节点操作
print(head);sort(head);print(head);

printf("\ninput the deleted number:");
scanf("%ld",&del_num);
while(del_num!=0)
{head=del(head,del_num);
print(head);
printf("input the deleted number:");
scanf("%ld",&del_num);}

//插入节点操作
printf("\ninputthe insertd record:");
stu=(struct student *)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
while(stu->num!=0)
{
head=insert(head,stu);
print(head);
printf("input the inserted record:");
stu=(struct student *)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
}
}