c语言实现的学生信息查询系统

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#define N 40
//输入要求：学号必须为正规学号（位数在8以上）
//姓名需输入英文全拼，尽量不写汉字
//密码为yangjiantao
typedef struct//结构体
{
    long num;//学号，长度要大于8位，
    char name[15];//姓名需输入英文全拼，尽量不写汉字
    unsigned int score[3];//成绩（百分制）
    float sumS;//每个学生的总成绩
    float aveS;//每个学生的平均分
} STU;

void input(STU person[],int m,int n);//输入学生的姓名，学号，成绩
void a(STU person[],int sumc[],float avec[],int m,int n);//计算学生的总分及平均分
void print(STU person[],int sumc[],float avec[],int m,int n);//输出学生的信息以及每门课的总分
void sort1(STU person[],int m,int n);//按成绩由小到大排序
void print1(STU person[],int m,int n,int min[]);//按成绩由小到大输出成绩
void print2(STU person[],int m,int n,int min[]);//按成绩由大到小输出成绩
void sort3(STU person[],int m,int n,int min[]);//按学号由小到大排序
void print3(STU person[],int m,int n,int min[]);//按学号由小到大输出成绩
void sort4(STU person[],int m,int n,int min[]);//按姓名字母顺序排序
void print4(STU person[],int m,int n,int min[]);//按姓名字母顺序输出成绩
int numsearch(STU person[],int m,long x);//x为学号
int namesearch(STU person[],int m,char y[]);//y为姓名
void writetofile(STU person[],int n);//向文件写入数据
void readfromfile(STU person[]);//从文件读出数据并打印出成绩

int main()
{
    char s[100]="hello",ch[100];
    printf("WHO ARE YOU?\n");
          gets(ch);
  system("cls");
    if(strcmp(s,ch)==0)//密码设置
    {
        int m,n,sumc[N],min[N],y;//m,n为总人数与总科目数,n=3,sumc为每门课的总分，min为名次
        float avec[N];//每门课的平均分
        STU person[N];//定义结构体数组
        printf("INPUT TOTAL NUMBER OF STUDENTS AND COURSES(courses==3):\n");
        scanf("%d %d",&m,&n);
        printf("INPUT YOUR NUMBER  AND  NAME\n");
        printf("YOUR NUMBER MUST HAVE 8--14 DIGITS,AND YOUR NAME USE SPELLING\n");
        input(person,m,n);
        a(person,sumc,avec,m,n);
        sort1(person,m,n);
        sort3(person,m,n,min);
        sort4(person,m,n,min);
        printf("1.Sort in ascending order by total score of every of every student\n");//用户选项1--10
        printf("2.Sort in descending order by total score of every of evedy student\n");
        printf("3.Sort in ascending order by number\n");
        printf("4.Sort in dictionary order by name\n");
        printf("5.Search by number\n");
        printf("6.search by name\n");
        printf("7.Statics analysis for every course\n");
        printf("9.Write to a file\n");
        printf("10.Read from a file\n");
        printf("0.Exit\n");//退出程序
        while(1)
        {
            printf("Please enter your choice:");
            scanf("%d",&y);//输入选择
            if(y==1)
            {
                printf("              GRADE  ASDENDING\n");
                print1(person,m,n,min);
            }
            else if(y==2)
            {
                printf("             GRADE  DESCENDING\n");
                print2(person,m,n,min);
            }
            else if(y==3)
            {
                printf("              NUM ASDENDING\n");
                print3(person,m,n,min);
            }
            else if(y==4)
            {
                printf("              NAME ASDENDING\n");
                print4(person,m,n,min);
            }
            else if(y==5)
            {
                long x;
                char ch;
                do
                {
                    printf("INPUT YOUR SEARCHING NUMBER\n");
                    scanf("%ld",&x);
                    int p;
                    p=numsearch(person,m,x);
                    if(p!=-1)
                    {
                        printf("%ld   %s  %u %u  %u  %.0f  %d\n",person[p].num,person[p].name,person[p].score[0],
                               person[p].score[1],person[p].score[2],person[p].sumS,min[p]);
                    }
                    else printf("NO THIS STUDENT\n");
                    printf("Do you want do it again? Please enter y,Y,n,N\n");
                    scanf(" %c",&ch);//空格消去前面的回车
                }
                while(ch=='y'||ch=='Y');
            }
            else if(y==6)
            {
                char y[19];
                int ch;
                do
                {
                    printf("INPUT YOUR SEARCHING NAME\n");
                    getchar();//消掉前面的回车
                    gets(y);
                    int r;
                    r=namesearch(person,m,y);
                    if(r!=-1)
                    {
                        printf("%ld   %s  %u %u  %u  %.0f  %d\n",person[r].num,person[r].name,person[r].score[0],
                               person[r].score[1],person[r].score[2],person[r].sumS,min[r]);
                    }
                    else printf("NO THIS STUDENT\n");
                    printf("Do you want do it again? Please enter 1 or 0\n");
                    scanf("%d",&ch);
                }while(ch==1);
            }
            else  if(y==8)
            {
                printf("                    TOTAL STATE\n");
                print(person,sumc,avec,m,n);
            }
            else if(y==9)
            {
                writetofile(person,n);
            }
            else if(y==10)
            {
                readfromfile(person);
                print1(person,m,n,min);
            }
            else if(y==0)  exit(0);//退出程序
            else printf("                           NO THIS CHOICE!!!\n");
        }
    }
    else
        printf("you are a bad man\n"),exit(0);
    return 0;
}

void input(STU person[],int m,int n)//输入学生的姓名，学号，成绩
{
    int i,j;
    for(i=0; i<m; i++)
    {
        person[i].sumS=0;
        scanf("%ld %s",&person[i].num,person[i].name);
        int l=strlen(person[i].name);
        if(l>=8&&l<=14)//判断姓名的长度
        {
           printf("INPUT THE GRADES OF COURSES as MT EN PH\n");
            for(j=0; j<n; j++)
            {
                scanf("%u",&person[i].score[j]);
                person[i].sumS=person[i].sumS+person[i].score[j];
            }
            person[i].aveS=person[i].sumS/n;
        }
        else
        {
            printf("YOUR NAME IS INFORMAL!!!PLEASE ENTER IT AGAIN!!!\n");
            printf("IT MUST HAVE 8--14 ALPHAS\n");
            i--;
        }
    }
}

void a(STU person[],int sumc[],float avec[],int m,int n)//计算学生的总分及平均分
{
    int i,j;
    for(i=0; i<n; i++)
    {
        sumc[i]=0;
        for(j=0; j<m; j++)
        {
            sumc[i]=sumc[i]+person[j].score[i];
        }
        avec[i]=sumc[i]/m;
    }
}

void print(STU person[],int sumc[],float avec[],int m,int n)//输出学生的信息以及每门课的总分
{
    int i,j;
    for(i=0; i<m; i++)
    {
        printf("%13ld%15s  ",person[i].num,person[i].name);
        for(j=0; j<n; j++)
        {
            printf("%d\t",person[i].score[j]);
        }
        printf("%.0f\t%.1f\n",person[i].sumS,person[i].aveS);
    }
    printf("Sumofcourse\t\t\t");
    for(j=0; j<n; j++)
    {
        printf("%d\t",sumc[j]);
    }
    printf("\nAveofcourse\t\t\t");
    for(j=0; j<n; j++)
    {
        printf("%.1f\t",avec[j]);
    }
    printf("\n");
}

void sort1(STU person[],int m,int n)//按成绩由小到大排序
{
    int i,j;
    STU temp;//temp为中间变量
    for(i=1; i<m; i++)//冒泡排序
    {
        for(j=0; j<=m-i-1; j++)
        {
            if(person[j].sumS>person[j+1].sumS)
            {
                temp=person[j+1];
                person[j+1]=person[j];
                person[j]=temp;
            }
        }
    }
}

void print1(STU person[],int m,int n,int min[])//按成绩由小到大输出成绩
{
    int i,j,k=m;
    printf("Number\t     Name\t    MT  EN  PH  SUM  RANK\n");
    for(i=0; i<m; i++)
    {
        printf("%.ld%13s   ",person[i].num,person[i].name);
        for(j=0; j<n; j++)
        {
            printf("%4d",person[i].score[j]);
        }
        printf("   %.0f\t",person[i].sumS);
        min[i]=k;
        k--;
        printf("%d\n",min[i]);
    }
}

void print2(STU person[],int m,int n,int min[])//按成绩由大到小输出成绩
{
    int i,j;
    printf("Number\t     Name\t    MT  EN  PH  SUM  RANK\n");
    for(i=m-1; i>=0; i--)
    {
        printf("%.ld%13s   ",person[i].num,person[i].name);
        for(j=0; j<n; j++)
        {
            printf("%4d",person[i].score[j]);
        }
        printf("   %.0f\t",person[i].sumS);
        printf("%d\n",min[i]);
    }
}

void sort3(STU person[],int m,int n,int min[])//按学号由小到大排序
{
    int i,j;//temp，temp1为中间变量
    STU temp;
    int temp1;
    for(i=1; i<m; i++)
    {
        for(j=0; j<=m-i-1; j++)
        {
            if(person[j].num>person[j+1].num)
            {
                temp=person[j+1];

                person[j+1]=person[j];
                person[j]=temp;
                temp1=min[j+1];
                min[j+1]=min[j];
                min[j]=temp1;
            }
        }
    }
}

void print3(STU person[],int m,int n,int min[])//按学号由小到大输出成绩
{
    int i,j;
    for(i=0; i<m; i++)
    {
        printf("Number\t     Name\t    MT  EN  PH  SUM  RANK\n");
        printf("%.ld%13s   ",person[i].num,person[i].name);
        for(j=0; j<n; j++)
        {
            printf("%4d",person[i].score[j]);
        }
        printf("   %.0f\t",person[i].sumS);
        printf("%d\n",min[i]);
    }
}

void sort4(STU person[],int m,int n,int min[])//按姓名字母顺序排序
{
    int i,j,temp1;
    STU temp;
    for(j=1; j<m; j++)
    {
        for(i=0; i<=m-j-1; i++)
        {
            if(strcmp(person[i].name,person[i+1].name)>0)
            {
                temp=person[i+1];
                person[i+1]=person[i];
                person[i]=temp;
                temp1=min[i+1];
                min[i+1]=min[i];
                min[i]=temp1;
            }
        }
    }
}

void print4(STU person[],int m,int n,int min[])//按姓名字母顺序输出成绩
{
    int i,j;
    printf("Number\t     Name\t    MT  EN  PH  SUM  RANK\n");
    for(i=0; i<m; i++)
    {
        printf("%.ld%13s   ",person[i].num,person[i].name);
        for(j=0; j<n; j++)
        {
            printf("%4d",person[i].score[j]);
        }
        printf("   %.0f\t",person[i].sumS);
        printf("%d\n",min[i]);
    }
}

//按学号查询学生信息
int numsearch(STU person[],int m,long x)//x为学号
{
    int i;
    for(i=0; i<m; i++)
    {
        if(person[i].num==x)
            return i;
    }
    return -1;
}

//按姓名查找
int namesearch(STU person[],int m,char y[])//x为姓名
{
    int i;
    for(i=0; i<m; i++)
    {
        if(strcmp(y,person[i].name)==0)
            return i;
    }
    return -1;
}

void writetofile(STU person[],int n)//将学生信息写入文件
{
    FILE *fp;
    if((fp=fopen("1.txt","w"))==NULL)
    {
        printf("Faliure to open file\n");
        exit(0);
    }
    fwrite(person,sizeof(STU),n,fp);
    fclose(fp);
}

void readfromfile(STU person[])//从文件中读取学生信息并打印
{
    FILE *fp;
    int i;
    if((fp=fopen("1.txt","r"))==NULL)
    {
        printf("Faliure to open file\n");
        exit(0);
    }
    for(i=0; !feof(fp); i++)
    {
        fread(&person[i],sizeof(STU),1,fp);
    }
    fclose(fp);
}