C语言写了个学生成绩管理系统，有些小问题想请教一下
有很多小问题，能运行，但是菜单那些功能都不能实现，希望能有高手指点一下，万分感谢！#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <windows.h>
#include <conio.h>
#include <ctype.h>
typedef struct _Node
{
char szNo[3];
char szName[32];
char szSex[8]; //"man" or "woman"
int nChinese;
int nEnglish;
int nMath;
int nDesign;
int nJava;
int nTotal;
float nAvg;
struct _Node *next;
}Node, *pNode;
pNode head = NULL;
void gotoxy(int x, int y) //移动光标位置函数
{
COORD pos;
pos.X = x - 1;
pos.Y = y - 1;
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),pos);
}
void load(void) //开始及登陆界面
{
int n = 0;
FILE *fp1, *fp2;
char name[20];
char loadingname[20];
char password[20];
char loadingpassword[20];
gotoxy(20, 3);
printf("---------欢迎使用学生成绩管理系统---------"); //开始界面
fp1 = fopen("d:\\用户名.txt", "r"); //打开用户名文件
fp2 = fopen("d:\\密码.txt", "r"); //打开密码文件
if (fp1 == NULL || fp2 == NULL) //打开文件有错
{
system("cls");
gotoxy(33, 8);
printf("打开文件出错");
gotoxy(33,10);
printf("程序将自动结束");
gotoxy(33,12);
exit(1);
}
else
{
gotoxy(32, 9); //开始用户名输入
printf("请输入用户名和密码");
gotoxy(25, 13);
printf("用户名:");
gotoxy(25, 15);
printf("密 码:");
gotoxy(36, 13);
scanf("%s", name);
gotoxy(36, 15); //完成对密码和用户名的输入
while(n < 10 && password[n - 1] != '\r')
{
password[n++] = getch();
if (password[n-1] != '\b') //如果输入的不是退格
{
putchar('*');
}
else
{
if (n > 1) //当有输入密码时退格
{
printf("\b \b"); //把光标往回移动一格，打印一个空格，再往回移动一格
}
n = n - 2;
if (n < 0)
{
n = 0;
}
}
}
password[n - 1] = '\0';
n = 0;
fscanf(fp1, "%s", loadingname);
fscanf(fp2, "%s", loadingpassword);
if ((strcmp(name, loadingname) == 0) &&(strcmp(password, loadingpassword) == 0))
{
gotoxy(25, 17);
printf("用户名和密码输入正确，按回车键进入菜单");
fflush(stdin); //清空输入缓冲
getchar();
system("cls");
}
else
{
system("cls");
gotoxy(34, 10);
printf("用户名或密码错误！");
gotoxy(39, 12);
printf("程序关闭");
gotoxy(30, 14);
exit(0);
}
system("cls");
}
fclose(fp1);
fclose(fp2);
}
void CreateNode(Node data)
{
char szData[1024] = "\0";
FILE *fp = NULL;
pNode temp = (pNode)malloc(sizeof(Node));
strcpy(temp->szNo, data.szNo);
strcpy(temp->szName, data.szName);
strcpy(temp->szSex, data.szSex);
temp->nChinese = data.nChinese;
temp->nEnglish = data.nEnglish;
temp->nMath = data.nMath;
temp->nDesign = data.nDesign;
temp->nJava = data.nJava;
temp->nTotal = temp->nChinese + temp->nEnglish + temp->nMath + temp->nDesign + temp->nJava;
temp->nAvg = (float)temp->nTotal / 5;
temp->next = NULL;
sprintf(szData, "%s|%s|%s|%d|%d|%d|%d|%d|%d|%f\r\n", data.szNo, data.szName, data.szSex,
data.nChinese, data.nMath, data.nEnglish, data.nDesign, data.nJava, temp->nTotal, temp->nAvg);
fp = fopen("D:\\Data.txt", "ab+");
fputs(szData, fp);
fclose(fp);
if(NULL == head)
{
head = temp;
}
else
{
pNode p = head->next;
while(p != NULL)
{
p = p->next;
}
p->next = temp;
}
system("cls");
}
//返回1表示不存在更改的这个节点
int UpdateNode(Node data)
{
char szData[1024] = "\0";
pNode temp = NULL;
if(NULL == head)
return 1;
temp = head;
while(0 != strcmp(temp->szNo, data.szNo) && NULL != temp)
{
temp = temp->next;
}
if(NULL == temp)
{
return 1;
}
strcpy(temp->szNo, data.szNo);
strcpy(temp->szName, data.szName);
strcpy(temp->szSex, data.szSex);
temp->nChinese = data.nChinese;
temp->nEnglish = data.nEnglish;
temp->nMath = data.nMath;
temp->nDesign = data.nDesign;
temp->nJava = data.nJava;
temp->nTotal = temp->nChinese + temp->nEnglish + temp->nMath + temp->nDesign + temp->nJava;
temp->nAvg = temp->nTotal / 5;
system("cls");
return 0;
}
int DeleteNode(char *pNo)
{
char szData[1024] = "\0";
pNode back = NULL;
pNode temp = NULL;
if(NULL == head)
return 1;
if(0 == strcmp(head->szNo, pNo))
{
if(NULL == head->next)
{
free(head);
head = NULL;
return 0;
}
else
{
temp = head;
head = head->next;
free(temp);
return 0;
}
}
back = head;
temp = head->next;
while(0 == strcmp(temp->szNo, pNo) && NULL != temp)
{
back = back->next;
temp = temp->next;
}
if(NULL == temp)
return 1;
back->next = temp->next;
free(temp);
temp = NULL;
system("cls");
return 0;
}
pNode QueryForNo(char *pNo)
{
pNode temp = NULL;
if(NULL == head)
return NULL;
if(0 == strcmp(head->szNo, pNo))
{
return head;
}
temp = head->next;
while(0 == strcmp(temp->szNo, pNo) && NULL != temp)
{
temp = temp->next;
}
if(NULL == temp)
return NULL;
return temp;
}
void Input(pNode data)
{
printf("Number:");
scanf("%s", data->szNo);
printf("Name:");
scanf("%s", data->szName);
printf("Sex:");
scanf("%s", data->szSex);
printf("Chinese:");
scanf("%d", &data->nChinese);
printf("Math:");
scanf("%d", &data->nMath);
printf("English:");
scanf("%d", &data->nEnglish);
printf("Design:");
scanf("%d", &data->nDesign);
printf("Java:");
scanf("%d", &data->nJava);
}
void Print()
{
printf("|%8s", "Number");
printf("|%8s", "Name");
printf("|%5s", "Sex");
printf("|%s", "Chinese");
printf("|%s", "Math");
printf("|%s", "English");
printf("|%s", "Design");
printf("|%s", "Java");
printf("|%s", "Total");
printf("|%s", "Avg");
printf("\n");
}
void Output(pNode data)
{
printf("|%8s", data->szNo);
printf("|%8s", data->szName);
printf("|%5s", data->szSex);
printf("|%7d", data->nChinese);
printf("|%4d", data->nMath);
printf("|%7d", data->nEnglish);
printf("|%6d", data->nDesign);
printf("|%4d", data->nJava);
printf("|%5d", data->nTotal);
printf("|%f", data->nAvg);
printf("\n");
}
void OutputLowAvg()
{
int nTotalChinese = 0;
int nTotalMath = 0;
int nTotalEnglish = 0;
int nTotalDesign = 0;
int nTotalJava = 0;
int nCount = 0;
float avgChinese = 0.0;
float avgMath = 0.0;
float avgEnglish = 0.0;
float avgDesign = 0.0;
float avgJava = 0.0;
pNode temp = head;
if(temp == NULL)
{
printf("无信息！\n");
return;
}
while(NULL != temp)
{
nTotalChinese += temp->nChinese;
nTotalMath += temp->nMath;
nTotalEnglish += temp->nEnglish;
nTotalDesign = temp->nDesign;
nTotalJava = temp->nJava;
nCount ++;
temp = temp->next;
}
avgChinese = (float)nTotalChinese/nCount;
avgMath = (float)nTotalMath/nCount;
avgEnglish = (float)nTotalEnglish/nCount;
avgDesign = (float)nTotalDesign/nCount;
avgJava = (float)nTotalJava/nCount;
temp = head;
while(NULL != temp)
{
if(temp->nChinese < (int)avgChinese ||
temp->nEnglish < (int)avgEnglish ||
temp->nMath < (int)avgMath ||
temp->nDesign < (int)avgDesign ||
temp->nJava < (int)avgJava)
{
Output(temp);
}
temp = temp->next;
}
}
void OutputUp90orLow60()
{
pNode temp = head;
if(temp == NULL)
{
printf("无信息！\n");
return;
}
while(NULL != temp)
{
if(temp->nChinese > 90 || temp->nChinese < 60 ||
temp->nMath > 90 || temp->nMath < 60 ||
temp->nEnglish > 90 || temp->nEnglish < 60 ||
temp->nDesign > 90 || temp->nDesign < 60 ||
temp->nJava > 90 || temp->nJava < 60)
{
Output(temp);
}
temp = temp->next;
}
}
void CreateList()
{
char szData[1024] = "\0";
pNode temp = NULL, p = NULL;
FILE *fp = fopen("D:\\Data.txt", "r");
if(NULL == fp)
return ;
while(fgets(szData, 1024, fp))
{
temp = (pNode)malloc(sizeof(Node));
sscanf(szData, "%[^|]|%[^|]|%[^|]|%d|%d|%d|%d|%d|%d|%f", temp->szNo, temp->szName, temp->szSex,
&temp->nChinese, &temp->nMath, &temp->nEnglish, &temp->nDesign, &temp->nJava, &temp->nTotal, &temp->nAvg);
temp->next = NULL;
if(NULL == head)
{
head = temp;
p = head;
continue;
}
p->next = temp;
p = temp;
}
fclose(fp);
}
int main ()
{
char szUserName[128] = "\0";
char szPassword[128] = "\0";
char szUser[128] = "\0";
char szPass[128] = "\0";
char szChoose[8] = "\0";
Node data;
char szNo[32] = "\0";
int nChoose = 0;
pNode temp = NULL;
load();
while(1)
{
memset(&data, 0, sizeof(data));
gotoxy(27,3);
printf("菜 单\n");
printf("\n\t*************************************************\n");
printf("\t\t1 增加学生信息\n");
printf("\t\t2 修改学生信息\n");
printf("\t\t3 删除学生信息\n");
printf("\t\t4 查找学生信息\n");
printf("\t\t5 输出统计数据\n");
printf("\t\t6 输出低于平均分的学生信息\n");
printf("\t\t7 输出高于90分和低于60分的学生信息\n");
printf("\t\t8 退出\n");
printf("\t*************************************************\n");
printf("\n请选择:");
scanf("%s", szChoose);
nChoose = atoi(szChoose);
if(nChoose < 1 || nChoose > 8)
{
printf("输入有误！\n请选择:");
continue;
}
switch(nChoose)
{
case 1:
Input(&data);
CreateNode(data);
break;
case 2:
Input(&data);
if(1 == UpdateNode(data))
printf("无该学生信息！\n");
else
printf("修改成功！\n");
break;
case 3:
printf("请输入要修改的学生学号:");
scanf("%s", szNo);
if(1 == DeleteNode(szNo))
printf("无该学生信息！\n");
else
printf("删除成功！\n");
szNo[0] = '\0';
break;
case 4:
printf("请输入要查找的学生学号:");
scanf("%s", szNo);
temp = QueryForNo(szNo);
if(temp == NULL)
printf("无该学生信息！\n");
else
Output(temp);
temp = NULL;
break;
case 5:
Print();
temp = head;
while(NULL != temp)
{
Output(temp);
temp = temp->next;
}
break;
case 6:
Print();
OutputLowAvg();
break;
case 7:
Print();
OutputUp90orLow60();
break;
}
printf("\n\n");
}
system( "pause");
return 0;
}
