. . . . .#includestdio.h#includestdlib.h#includeconio.h#includestring.h#includewindows.h /登陆界面函数void load();void background1();void choice1();void fanhui1();void denglu();void zhuce();int chazhao(); /目录界面函数void mulu();void background();void choice();void add();void xiugai();void shanchu();void del();void chaxun();void paixu();void tongji();void output();void finish();void fanhui2();void shuchu();int zongren();int chr();int enr();int mar();void back();float chinese();float english();float math();float zongmax(); /登陆界面结构体struct selfchar a10;char b10;int flg;s100=admin,admin,1,1,1,1; /目录界面结构体struct studentchar num10;char name10;float chinese;float english;float math;float sum;int a;stu5=1100,小明,12,18,20,50,1,1101,小样,20,80,60,160,1; /登陆界面void main()load();void load()background1();choice1();void background1()puts( );puts( );printf( *n);printf( 欢迎登录学生管理系统 );puts( );printf( *n);printf( 1.登录 2.注册 n );printf( 请选择:);void choice1()int a;scanf(%d,&a);fflush(stdin);switch(a)case 1:denglu();break;case 2:zhuce();break;default:fanhui1();break;void fanhui1()printf( 输入错误!n);printf( 请重新输入!n);system(cls);load();void denglu()struct self s2;char c;int i=0;int j=0;printf(请输入用户名:n);scanf(%s,s2.a);fflush(stdin);puts( );printf(请输入密码:);c=getch();while(c!=13)printf(*); s2.bi=c;i+;while(c=getch()=8)if(i=0)continue;putchar(b);putchar( );putchar(b);s2.b-i=0; s2.bi=0;s2.flg=1;puts( );puts(s2.b);for(i=0;i100;i+)if(!strcmp(si.a,s2.a)&!strcmp(si.b,s2.b)printf(成功!);system(cls);printf(nnnnnnnnnttt欢迎进入学生管理系统nnn);Sleep(2000);system(cls);mulu();elsej+;if(j=100)fanhui1();void zhuce()struct self s3;char c,d;int i,j;i=0;printf(请输入帐号:);gets(s3.a);puts(s3.a);printf(请输入密码:);c=getch();while(c!=13)printf(*); s3.bi=c;i+;while(c=getch()=8)if(i=0)continue;putchar(b);putchar( );putchar(b);s3.b-i=0;s3.bi=0;s3.flg=1;printf(确定y 取消n);scanf(%c,&d); fflush(stdin);if(d=y|d=Y)j=chazhao();sj=s3;printf(注册成功!);shuchu();system(cls);fanhui1();elsefanhui1();int chazhao()int a,i;for(i=0;i100;i+)if(si.flg=0)a=i;break;return i; /目录界面void mulu()background();choice();void background()printf(*n);printf(/_ n);printf(*n);puts( );printf(欢迎进入学生成绩管理系统);puts( );printf(*n);printf( 请输入业务:n);puts( );printf(1. 查看所有记录显示n);printf(2. 添加学生成绩n);printf(3. 修改学生成绩n);printf(4. 删除学生成绩n);printf(5. 清空记录n);printf(6. 按要求查询学生成绩n);printf(7. 按要求排序n);printf(8. 按要求统计成绩n);printf(9. 退出n);printf(请选择:);void choice()int a;scanf(%d,&a);fflush(stdin);printf(%dn,a);switch(a)case 1: output();break;case 2: add();break;case 3: xiugai();break;case 4: shanchu();break;case 5:del();break;case 6: chaxun();break;case 7: paixu();break;case 8: tongji();break;case 9:finish();break;default:system(cls);mulu();break;void add()system(cls);int i;char c,a;shuchu();printf(1 输入 2 返回主界面n);scanf(%d,&a);fflush(stdin);if(a=1)for(i=0;i5;i+)if(stui.a=0)break;printf(请输入学号:);scanf(%s,stui.num);fflush(stdin);printf(n请输入姓名:);scanf(%s,stui.name);fflush(stdin);printf(n请输入语文成绩:);scanf(%f,&stui.chinese);fflush(stdin);printf(n请输入英语成绩:);scanf(%f,&stui.english);fflush(stdin);printf(n请输入数学成绩:);scanf(%f,&stui