#include"stdio.h"
#include<string.h>
#include<stdlib.h>


#define N 30
struct student
{
    int num;
    char name[20];
    int age;
    int Math;
    int English;
    int Physical;
    long int sum;
}stu[N];

enter()
{
    int i,n;
    printf("How many students(1-%d)?:",N);
    scanf("%d",&n);
    printf("\nEnter data now\n\n");
    for(i=0;i<n;i++)
    {
        printf("\n Input %dth student record.\n",i+1);
        input(i);
    }
    if(i!=0) save(n);
    printf_back();  /* browse or back */
}

add()
{
    int i,n,m,k;
    FILE *fp;
    n=load();
    printf("How many students are you want to add(1-%d)?:",N-n);
    scanf("%d",&m);
    k=m+n;
    for(i=n;i<k;i++)
    {
        printf("\n Input %dth student record.\n",i+1);
        input(i);
    }
    if((fp=fopen("score.txt","ab"))==NULL)
    {
        printf("Cannot open file.\n");
    }
    for(i=n;i<k;i++)
        if(fwrite(&stu[i],sizeof(struct student),1,fp)!=1)
            printf("file write error.\n");
        fclose(fp);
        printf_back();
}

/* insert()
{int n,c;
struct student s;
n=load();
puts("\n Input one data.\n");
do
{input(n);
printf_face();
printf_one(n);
printf("\n\nAre you sure?\n\n\t 1.Sure\t2.cancel and again\t3.Back without save [ ]\b\b");
scanf("%d",&c);
if(c==1)
{
save(n+1);
printf_back();
}
else if(c!=2) menu();
}
while(c==2);
}  */

modify()
{
    struct student s;
    FILE *fp;
    int i,n,k,w0=1,w1,w2=0;
    n=load();
    do
    {
        k=-1;
        printf_face();
        for(i=0;i<n;i++)
        {
            if((i!=0)&&(i%10==0))
            {printf("\n\nRemember NO.031073- which needed modify.Pass any key to continue ...");
            getch();
            puts("\n\n");
            }
            printf_one(i);
            printf("\n");
        }
        do
        {
            printf("\n\nEnter NO.031073- that you want to modify!  NO.:031073-");
            scanf("%d",&s.num);
            for(i=0;i<n;i++)
                if(s.num==stu[i].num)
                {
                    k=i;
                    s=stu[i];  /* chengji beifei */
                }
                if(k==-1) printf("\n\nNO exist!please again");
        }
        while(k==-1);
        printf_face();
        printf_one(k);
        w1=modify_data(k,n);
        if(w1==1)
        {
            printf("\nSuccessful ^_^.\n\nAre you modify another?\n\n\t1.Yes2.Back with save\t[ ]\b\b");
            scanf("%d",&w0);
            w2=1;
        }
        else
        {
            w0=0;      /* end */
            if(w2==1)
                stu[k]=s;
        }
        if(w0!=1&&w2==1) save(n);  /* w0!=1 return    w2==1 modify */
    }
    while(w0==1);
    menu();
}

delete()
{
    struct student s;
    FILE *fp;
    int i,n,k,w0=1,w1,w2=0;
    n=load();
    do
    {
        k=-1;
        printf_face();
        for(i=0;i<n;i++)
        {if((i!=0)&&(i%10==0))
        {
            printf("\n\nRemember NO.031073- which needed delete.Pass any key to continue ...");
            getch();
            puts("\n\n");
        }
        printf_one(i);
        printf("\n");
        }
        do
        {
            printf("\n\nEnter NO.031073- that you want to delete!  NO.:031073-");
            scanf("%d",&s.num);
            for(i=0;i<n;i++)
                if(s.num==stu[i].num)
                {
                    k=i;
                    s=stu[i];  /* chengji beifei */
                }
                if(k==-1) printf("\n\nNO exist!please again");
        }
        while(k==-1);
        printf_face();
        printf_one(k);
        printf("\nAre you sure?\n\n\t1.Sure2.Back without save in this time [ ]\b\b");
        scanf("%d",&w1);
        if(w1==1)
        {
            stu[k].sum=0;
            printf("\nSuccessful ^_^.\n\nAre you delete another?\n\n\t1.Yes2.Back with save\t[ ]\b\b");
            scanf("%d",&w0);
            w2=1;
        }
        else
        {
            w0=0;      /* end */
            if(w2==1)
                stu[k]=s;
        }
        if(w0!=1&&w2==1) save(n);
    }
    while(w0==1);
    menu();
}



modify_score()
{
    struct student s;
    FILE *fp;
    int i,n,k,w0=1,w1,w2=0;
    n=load();
    do
    {
        k=-1;
        printf_face();
        for(i=0;i<n;i++)
        {
            if((i!=0)&&(i%10==0))
            {printf("\n\nRemember NO.031073 which score needed modify.Pass any key to continue ...");
            getch();
            puts("\n\n");
            }
            printf_one(i);
            printf("\n");
        }
        do
        {
            printf("\n\nEnter NO.031073- that you want to modify!  NO.:031073-");
            scanf("%d",&s.num);
            for(i=0;i<n;i++)
                if(s.num==stu[i].num)
                    
                {
                    k=i;
                    s=stu[i];  /* chengji beifei */
                }
                if(k==-1) printf("\n\nNO exist!please again");
        }
        while(k==-1);
        printf_face();
        printf_one(k);
        w1=modify_score1(k);
        if(w1==1)
        {
            printf("\nSuccessful ^_^.\n\nAre you modify another score?\n\n\t1.Yes2.Back with save\t[ ]\b\b");
            scanf("%d",&w0);
            w2=1;
        }
        else
        {
            w0=0;      /* end */
            if(w2==1)
                stu[k]=s;
        }
        if(w0!=1&&w2==1) save(n);  /* w0!=1 return    w2==1 modify */
    }
    while(w0==1);
    menu();
}

order()
{
    int i,j,k,n;
    struct student s;
    n=load();
    for(i=0;i<n-1;i++)
    {
        k=i;
        for(j=i+1;j<n;j++)
            if(stu[j].num<stu[k].num) k=j;
            s=stu[i];stu[i]=stu[k];stu[k]=s;
    }
    save(n);
    puts("\n\n");
    printf_back();
}

browse()
{
    int i,j,n;
    n=load();
    printf_face();
    for(i=0;i<n;i++)
    {
        if((i!=0)&&(i%10==0))
        {
            printf("\n\nPass any key to contiune ...");
            getch();
            puts("\n\n");
        }
        printf_one(i);
        printf("\n");
    }
    printf("\tThere are %d record.\n",n);
    printf("\nPass any key to back...");
    getch();
    menu();
}




save(int n)
{
    FILE *fp;
    int i;
    if((fp=fopen("score.txt","wb"))==NULL)
    {
        printf("\nCannot open file\n");
        return NULL;
    }
    for(i=0;i<n;i++)
        if(stu[i].sum!=0)
            if(fwrite(&stu[i],sizeof(struct student),1,fp)!=1)
                printf("file write error\n");
            fclose(fp);
}

load()
{
    FILE *fp;
    int i;
    if((fp=fopen("score.txt","rb"))==NULL)
    {printf("\nCannot open file\n");
    return NULL;
    }
    for(i=0;!feof(fp);i++)
        fread(&stu[i],sizeof(struct student),1,fp);
    fclose(fp);
    return(i-1);
}

no_input(int i,int n)
{
    int k,w1;
    do
    {
        w1=0;
        printf("NO.:031073-");
        scanf("%d",&stu[i].num);
        if(stu[i].num<1 || stu[i].num>N)
        {
            puts("Input error! Only be made up of(1-N).Please reinput!\n");
            w1=1;
        }
        if(w1!=1)
            for(k=0;k<n;k++)
                if(k!=i&&(stu[k].num==stu[i].num))
                {puts("This record is exist. Please reinput!\n");
                w1=1;break;
                }
    }
    while(w1==1);
}


enter_score(int i)
{
    printf("Math  English  Physical");
    scanf("%d %d %d",&stu[i].Math,&stu[i].English,&stu[i].Physical);
}
sum(int i)
{
    stu[i].sum=stu[i].Math+stu[i].English+stu[i].Physical;
}

input(int i)
{
    no_input(i,i);
    printf("name:   age:");
    scanf("%s %d",stu[i].name,&stu[i].age);
    enter_score(i);
    sum(i);
}



modify_score1(int i)
{
    int c,w1;
    do
    {
        puts("\nmodify by=>\n\n 1.Math 2.English 3.Physical4.all score 5.cancel and back");
        printf("Which you needed?:[ ]\b\b");
        scanf("%d",&c);
        if(c>5||c<1)
        {puts("\nChoice error! Please again!");
        getchar();
        }
    }
    while(c>5||c<1);
    do
    {
        switch(c)
        {
        case 1:printf("Math:");scanf("%d",&stu[i].Math);break;
        case 2:printf("English:");scanf("%d",&stu[i].English);break;
        case 3:printf("Physical:");scanf("%d",&stu[i].Physical);break;
        case 4:enter_score(i);break;
        case 5:break;
        }
        if(c>0&&c<5) sum(i);
        puts("\nNow:\n");
        printf_face();
        printf_one(i);
        printf("\nAre you sure?\n\n\t1.Sure 2.No and remodify3.Back without save in this time [ ]\b\b");
        scanf("%d",&w1);
    }
    while(w1==2);
    return(w1);
}

modify_data(int i,int n)
{
    int c,w1;
    do
    {
        puts("\nmodify by=>\n\n 1.NO. 2.name 3.age 4.Math 5.English 6.Physical7.all score 8.all data 9.cancel and back");
        printf("Which you needed?:[ ]\b\b");
        scanf("%d",&c);
        if(c>9||c<1)
        {
            puts("\nChoice error! Please again!");
            getchar();
        }
    }
    while(c>9||c<1);
    do
    {
        switch(c)
        {
        case 1:no_input(i,n);break;
        case 2:printf("name:");scanf("%s",stu[i].name);break;
        case 3:printf("age:");scanf("%d",&stu[i].age);break;
        case 4:printf("Math:");scanf("%d",&stu[i].Math);break;
        case 5:printf("English:");scanf("%d",&stu[i].English);break;
        case 6:printf("Physical:");scanf("%d",&stu[i].Physical);break;
        case 7:enter_score(i);break;
        case 8:input(i);break;
        case 9:break;
        }
        if(c>3&&c<8) sum(i);
        puts("\nNow:\n");
        printf_face();
        printf_one(i);
        printf("\nAre you sure?\n\n\t1.Sure 2.No and remodify3.Back without save in this time [ ]\b\b");
        scanf("%d",&w1);
    }
    while(w1==2);
    return(w1);
}

printf_face()
{
    printf("\nNO.031073  name   age  Math  English  Physical  sum\n");
}

printf_one(int i)
{
    printf("%6d %8s %4d",stu[i].num,stu[i].name,stu[i].age);
    printf("%5d %5d %8d %10d",stu[i].Math,stu[i].English,stu[i].Physical,stu[i].sum);
}

printf_back()
{
    int k,w;
    printf("\n\n\tSuccessful.^_^\n\n");
    printf("What do you want to do?\n\n\t1.Browse all now\t2.Back:[ ]\b\b");
    scanf("%d",&w);
    if(w==1) browse();
    else menu();
}
menu()
{
    int w1;
    char n;
    do
    {
        puts("\t\t****************MENU****************\n\n");
        puts("\t\t\t\tA.Enter new data");
        puts("\t\t\t\tB.Addition data");
        puts("\t\t\t\tC.Modify data");
        puts("\t\t\t\tD.Delete data");
        puts("\t\t\t\tE.Modify score");
        puts("\t\t\t\tF.Order by number");
        puts("\t\t\t\tG.Browse all");
        puts("\t\t\t\tH.Exit");
        puts("\n\n\t\t************************************\n");
        printf("Choice your number(A-H):[ ]\b\b");
        n=getchar();
        printf("\n");
        if(n<'A'||n>'H')
            w1=1;
        else w1=0;
    }
    while(w1==1);
    switch(n)
    {
    case 'A':enter();break;
    case 'B':add();break;
    case 'C':modify();break;
    case 'D':delete();break;
    case 'E':modify_score();break;
    case 'F':order();break;
    case 'G':browse();break;
    case 'H':exit(0);
    }
}
char password[7]="123456";
main()
{   
    char s[7];
    printf("\t\t请输入密码:\n\t\t\n\t\t");
    scanf("%s",s);
    if(!strcmp(s,password))
    {
        printf("\n\t\t恭喜你进入学生成绩管理系统\n");
        menu();
    }
    else
    {   
        printf("\t\t 密码错误\n\n");
        main();
    }




//别的我帮不了你，不过写代码注意格式....