采用链表实现的，自己编译运行通过。编译环境ubuntu+gcc4.8.4
如果想少输入几个人员信息看看效果，就将pernum的值修改大些，当然不要大于1
#include <stdio.h>
#define pernum 0.05
//定义结构体，该结构体被用来存储总分及平均分，为了保存函数calStuMarkByNo以及函数calStuMarkByStu的返回值
struct sumandavg
{
int allmark;
int avgmark;
};
//定义结构体，用以存储各科成绩
struct stumark
{
int englishmark;
int mathmark;
int cppmark;
};
//定义结构体，包括学生信息以及一个各科成绩的结构体变量，以及一个Next指针
struct student
{
char* stuno;
char* name;
char* classname;
struct stumark mark;
struct student* next;
};
//定义两个结构体指针，一个为链表头指针，一个为指向当前正在操作的结构体变量
struct student* head=NULL;
struct student* current=NULL;
//将学生变量添加到链表，参数为指向student结构体变量的指针
void addStudent(struct student* stu)
{
if(head==NULL)
{
head=stu;
current=stu;
stu->next=NULL;
}
else
{
current->next=stu;
current=stu;
stu->next=NULL;
}
}
//从链表中删除学生，参数为学生的学号，未对不存在的学号进行提示，直接忽略
void deleteStudent(char* no)
{
struct student* ptr=head;
while(ptr!=NULL)
{
if(ptr->next!=NULL && !strcmp(ptr->next->stuno,no))
{
ptr->next=ptr->next->next;
return;
}
else if(ptr->next==NULL)
{
head=NULL;
ptr=NULL;
}
else
{
ptr=ptr->next;
}
}
}
//通过学生学号查询学生信息，参数为学生学号
void queryStuInfo(char* no)
{
struct student* ptr=head;
while(ptr!=NULL)
{
if(!strcmp(ptr->stuno,no))
{
printf("student no.:%s name:%s class:%s english mark:%d math mark:%d cpp mark:%d\n",
ptr->stuno,ptr->name,ptr->classname,ptr->mark.englishmark,ptr->mark.mathmark,ptr->mark.cppmark);
return;
}
else
{
ptr=ptr->next;
}
}
}
//修改学生信息，参数为学生学号
void changeStudentInfo(char* no)
{
struct student* ptr=head;
while(ptr!=NULL)
{
if(!strcmp(ptr->stuno,no))
{
queryStuInfo(no);
break;
}
else
{
ptr=ptr->next;
}
}
int menuid;
printf("please select the item which you want to change:\n\
1、学号\n\
2、姓名\n\
3、班级\n\
4、英语成绩\n\
5、数学成绩\n\
6、C++成绩\n\
0、放弃修改\n");
scanf("%d",&menuid);
switch (menuid) {
case 1:
{
printf("please input new student no.:\n");
char* tmp=(char*)malloc(20*sizeof(char));;
scanf("%s",tmp);
ptr->stuno=tmp;
break;
}
case 2:
{
printf("please input new student name:\n");
char* tmp=(char*)malloc(20*sizeof(char));;
scanf("%s",tmp);
ptr->name=tmp;
break;
}
case 3:
{
printf("please input new class:\n");
char* tmp=(char*)malloc(20*sizeof(char));;
scanf("%s",tmp);
ptr->classname=tmp;
break;
}
case 4:
{
printf("please input new english mark:\n");
int tmp;
scanf("%d",&tmp);
ptr->mark.englishmark=tmp;
break;
}
case 5:
{
printf("please input new math mark:\n");
int tmp;
scanf("%d",&tmp);
ptr->mark.mathmark=tmp;
break;
}
case 6:
{
printf("please input new cpp mark:\n");
int tmp;
scanf("%d",&tmp);
ptr->mark.cppmark=tmp;
break;
}
case 0:
{
return;
}
default:
break;
}
}
//计算单个学生成绩，包括总成绩及平均成绩，参数为学生学号，返回值为结构体sumandavg的指针
struct sumandavg* calStuMarkByNo(char* no)
{
struct student* ptr=head;
struct sumandavg tmpsamark;
while(ptr!=NULL)
{
if(!strcmp(ptr->stuno,no))
{
tmpsamark.allmark=ptr->mark.cppmark+ptr->mark.englishmark+ptr->mark.mathmark;
tmpsamark.avgmark=tmpsamark.allmark/3;
return &tmpsamark;
}
else
{
ptr=ptr->next;
}
}
return NULL;
}
//计算单个学生成绩，包括总成绩及平均成绩，参数为student结构体指针，返回值为sumandavg结构体的指针
struct sumandavg* calStuMarkByStu(struct student* stu)
{
struct sumandavg tmpsamark;
tmpsamark.allmark=stu->mark.cppmark+stu->mark.englishmark+stu->mark.mathmark;
tmpsamark.avgmark=tmpsamark.allmark/3;
return &tmpsamark;
}
/*获取学习标兵及三好学生，本打算通过链表排序来实现，奈何水平有限，对链表的操作不熟，只能用下面的方法了*/
void getFirstAndPer5()
{
struct student* ptr=head;
struct student* first=head;//用于保存最高分的信息
int stunum=0;
//通过while循环计算出学生数量
while(ptr!=NULL)
{
stunum++;
ptr=ptr->next;
}
//计算符合比例情况下，学习标兵以及三好学生的总数，然后malloc总数个结构体内存空间
int threegoodstu=stunum*pernum+1;
struct student* per5=(struct student*)malloc(threegoodstu*sizeof(struct student));
ptr=head;
int i=0;
//遍历链表，将符合要求的学生与first比较，比first大的替换掉first，这样first保持的就是总分最高的人，同时将所有符合要求的学生保存在分配好的内存中
while(ptr!=NULL)
{
if(ptr->mark.cppmark>=75 && ptr->mark.englishmark>=75 && ptr->mark.mathmark>=75)
{
struct sumandavg ptrsa,firstsa;
ptrsa.allmark=ptr->mark.cppmark+ptr->mark.mathmark+ptr->mark.englishmark;
firstsa.allmark=first->mark.cppmark+first->mark.englishmark+first->mark.mathmark;
if(ptrsa.allmark>firstsa.allmark)
{
first=ptr;
}
*(per5+i)=*ptr;
i++;
}
ptr=ptr->next;
}
printf("学习标兵:%s\n",first->stuno);
int j=0;
for(;j<i;j++)
{
if(strcmp((per5+j)->stuno,first->stuno))
{
printf("三好学生:%s\n",(per5+j)->stuno);
}
}
}
int main(void)
{
int menuid;
while(1)
{
if(head==NULL)
{
printf("1、添加学生信息\n0、退出\n");
}
else
{
printf("1、添加学生信息\n\
2、删除学生信息\n\
3、查询学生信息\n\
4、修改学生信息\n\
5、浏览所有学生信息\n\
6、查看所有学生总成绩及平均成绩\n\
7、查看“学习标兵”及“三好学生”\n\
0、退出\n");
}
scanf("%d",&menuid);
switch(menuid)
{
case 1:
{
struct student* tmpstu=(struct student*)malloc(sizeof(struct student));
printf("please input student no.:\n");
tmpstu->stuno=(char*)malloc(20*sizeof(char));
scanf("%s",tmpstu->stuno);
printf("please input the name:\n");
tmpstu->name=(char*)malloc(20*sizeof(char));
scanf("%s",tmpstu->name);
printf("please input student class:\n");
tmpstu->classname=(char*)malloc(20*sizeof(char));
scanf("%s",tmpstu->classname);
printf("please input the math mark:");
scanf("%d",&tmpstu->mark.mathmark);
printf("please input the english mark:");
scanf("%d",&tmpstu->mark.englishmark);
printf("please input the cpp mark:");
scanf("%d",&tmpstu->mark.cppmark);
addStudent(tmpstu);
break;
}
case 2:
{
printf("please input the student no. which you want to delete:\n");
char* tmpch=(char*)malloc(20*sizeof(char));
scanf("%s",tmpch);
deleteStudent(tmpch);
break;
}
case 3:
{
printf("please input the student no. which you want to query:\n");
char* tmpch=(char*)malloc(20*sizeof(char));
scanf("%s",tmpch);
queryStuInfo(tmpch);
break;
}
case 4:
{
printf("please input the student no. which you want to change:\n");
char* tmpch=(char*)malloc(20*sizeof(char));
scanf("%s",tmpch);
changeStudentInfo(tmpch);
break;
}
case 5:
{
struct student* ptr=head;
while(ptr!=NULL)
{
printf("student no.:%s name:%s class:%s english mark:%d math mark:%d cpp mark:%d\n",
ptr->stuno,ptr->name,ptr->classname,ptr->mark.englishmark,ptr->mark.mathmark,ptr->mark.cppmark);
ptr=ptr->next;
}
break;
}
case 6:
{
struct student* ptr=head;
while(ptr!=NULL)
{
struct sumandavg* tmpsa;
tmpsa=calStuMarkByStu(ptr);
printf("%s: totalscore:%d averagescore:%d\n",ptr->stuno,tmpsa->allmark,tmpsa->avgmark);
ptr=ptr->next;
}
break;
}
case 7:
{
getFirstAndPer5();
break;
}
case 0:
{
exit(0);
}
default:
continue;
}
}
}