学生成绩管理
1)每条记录包括:学号、姓名、专业和5门课程的成绩;
2)能够实现添加、删除、修改功能;
3)能够计算某学生的总分和平均分;
4)能按照总分排序输出。
书上不是有代码了吗,你有什么问题?
下面是我写的一个代码:
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define NMBSCORE 5
struct StNode
{
int num; //学号
char name[20]; //姓名
char partment[20]; //专业
int score[NMBSCORE]; //成绩
StNode* next;
};
//录入信息
struct StNode* Input(struct StNode* head)
{
struct StNode* p, * node;
int i;
system("cls");
node = (struct StNode*)malloc(sizeof(struct StNode));
//录入信息
printf("请输入学号:");
scanf("%d", &node->num);
printf("请输入姓名:");
scanf("%s", node->name);
printf("请输入专业:");
scanf("%s", node->partment);
printf("请输入%d门课程的成绩:", NMBSCORE);
for (i = 0; i < NMBSCORE; i++)
scanf("%d", &node->score[i]);
node->next = 0;
if (head == 0)
{
head = node;
//
}
else
{
p = head;
while (p->next)
p = p->next;
//新建节点
p->next = node;
}
system("pause");
return head;
}
//显示所有学生信息
void showAll(struct StNode* head)
{
struct StNode* p;
int i = 1, j;
system("cls");
p = head;
printf("学号 姓名 专业 五门课成绩\n");
while (p)
{
printf("%-4d ", p->num);
printf("%-8s ", p->name);
printf("%-10s ", p->partment);
for (j = 0; j < NMBSCORE; j++)
printf("%d ", p->score[j]);
printf("\n");
i++;
p = p->next;
}
system("pause");
}
//查询信息
void Find(struct StNode* head)
{
int opt;
struct StNode* p = head;
int id, j;
char name[20] = { 0 };
system("cls");
printf("1.按学号查询\n");
printf("2.按姓名查询\n");
scanf("%d", &opt);
switch (opt)
{
case 1:
printf("请输入学号:");
scanf("%d", &id);
while (p)
{
if (p->num == id)
{
printf("学生学号:%d\n", p->num);
printf("学生姓名:%s\n", p->name);
printf("学生专业:%s\n", p->partment);
printf("学生成绩:");
for (j = 0; j < NMBSCORE; j++)
printf("%d ", p->score[j]);
printf("\n");
break;
}
p = p->next;
}
if (p == 0)
printf("查无此人\n");
break;
case 2:
printf("请输入姓名:");
scanf("%s", name);
while (p)
{
if (strcmp(p->name, name) == 0)
{
printf("学生学号:%d\n", p->num);
printf("学生姓名:%s\n", p->name);
printf("学生专业:%s\n", p->partment);
printf("学生成绩:");
for (j = 0; j < NMBSCORE; j++)
printf("%d ", p->score[j]);
printf("\n");
break;
}
p = p->next;
}
if (p == 0)
printf("查无此人\n");
break;
}
system("pause");
}
//修改学生信息
void ModInfo(struct StNode* head)
{
struct StNode* node = 0;
int id, i;
system("cls");
printf("请输入需要修改信息的学生学号:");
scanf("%d", &id);
node = head;
while (node)
{
if (node->num == id)
break;
else
node = node->next;
}
if (node == 0)
printf("查无此人\n");
else
{
memset(node->name, 0, 20);
printf("请输入姓名:");
scanf("%s", node->name);
printf("请输入专业:");
scanf("%s", node->partment);
printf("请输入%d门课程的成绩:", NMBSCORE);
for (i = 0; i < NMBSCORE; i++)
scanf("%d", &node->score[i]);
}
system("pause");
}
//删除学生信息
void DeleteInfo(struct StNode* head)
{
struct StNode* node, * pre;
int id;
system("cls");
printf("请输入需要删除信息的学生学号:");
scanf("%d", &id);
if (head->num == id)
{
node = head->next;
free(head);
head = node;
printf("该学生信息已经删除\n");
system("cls");
return;
}
else
{
pre = head;
node = head->next;
while (node)
{
if (node->num == id)
{
pre->next = node->next;
free(node);
node = 0;
printf("该学生信息已经删除\n");
system("pause");
return;
}
else
{
pre = node;
node = node->next;
}
}
printf("查无此人\n");
system("pause");
}
}
//计算某学生的总分和平均分
void SumAndAve(struct StNode* head,int id, double *sum,double *ave)
{
struct StNode* node;
int i;
*sum = 0;
*ave = 0;
node = head;
while (node)
{
if (node->num == id)
{
for (i = 0; i < NMBSCORE; i++)
*sum += node->score[i];
*ave = *sum / NMBSCORE;
break;
}
else
node = node->next;
}
}
//排序
struct StNode* SortBySum(struct StNode* head)
{
struct StNode* min_pre = NULL;
struct StNode* min = head;
struct StNode* tmp = head;
struct StNode* new_list = NULL;
struct StNode* tail_sort = NULL;
double sum1, sum2, ave1, ave2;
if (NULL == head) //若链表为空则不用排序
{
return NULL;
}
if (NULL == head->next) //若链表中只有一个数,则不用比较
{
printf("min is head\n");
return head;
}
while (head)
{
min = head;
tmp = head;
while (tmp->next)
{
SumAndAve(head, min->num, &sum1, &ave1);
SumAndAve(head, tmp->next->num,&sum2,&ave2);
if (sum1 > sum2)
{
min = tmp->next;
min_pre = tmp;
}
tmp = tmp->next;
}
if (min == head)
{
head = head->next;
}
else
{
min_pre->next = min->next;
min->next = NULL;
}
if (NULL == new_list) //按照尾插将最小的数组成新的链表
{
tail_sort = min;
new_list = tail_sort;
}
else
{
tail_sort->next = min;
tail_sort = min;
}
}
return new_list;
}
int main()
{
struct StNode* head = 0;
int opt = 0;
int bgo = 1;
const char* filename = "students.txt";
double sum, ave;
int id;
while (bgo)
{
system("cls");
printf("--------------学生信息管理系统---------------|\n");
printf("| 1.录入学生信息 |\n");
printf("| 2.显示所有学生信息 |\n");
printf("| 3.学生信息查询 |\n");
printf("| 4.学生信息修改 |\n");
printf("| 5.学生信息删除 |\n");
printf("| 6.计算总分平均分 |\n");
printf("| 7.按总分排序 |\n");
printf("| 0.退出系统 |\n");
printf("----------------------------------------------\n");
scanf("%d", &opt);
switch (opt)
{
case 0:
bgo = 0;
break;
case 1:
head = Input(head);
break;
case 2:
showAll(head);
break;
case 3:
Find(head);
break;
case 4:
ModInfo(head);
break;
case 5:
DeleteInfo(head);
break;
case 6:
system("cls");
printf("请输入需要查询的学生id:");
scanf("%d", &id);
sum = -1;
SumAndAve(head,id,&sum,&ave);
if (sum == -1)
printf("查无此人!\n");
else
printf("sum=%g,ave=%g\n", sum, ave);
system("pause");
break;
case 7:
head = SortBySum(head);
printf("排序完成!\n");
system("pause");
break;
}
}
return 0;
}