/* Bai tap 1_61 - Quan ly danh sach hoc sinh */

#include <stdio.h>

#define MAX 100

typedef struct hocsinh {

char hoten[35];

char lop[7];

float diemtoan, diemly, diemhoa;

} HOCSINH;

HOCSINH danhsach[MAX];

int numrecords = 0;

char filename[] = "DANHSACH.DAT";

int menu()

{

char c;

clrscr();

printf("+----- Menu -----+");

printf("

+----------------+");

printf("

+ 1. Nhap +");

printf("

+ 2. Xoa +");

printf("

+ 3. Sua doi +");

printf("

+ 4. Liet ke +");

printf("

+----------------+");

printf("

+ 5. Luu len dia +");

printf("

+ 6. Lay tu dia +");

printf("

+----------------+");

printf("

+ 0. Thoat +");

printf("

+----------------+");

printf("

Chon muc : ");

do {

c = getch();

} while (c<'0' || c>'6');

return c-'0';

}

void nhapmoi()

{

int done = 0;

char hoten[35];

float diem;

do {

printf("

Ho ten (trong de thoat) : ");

gets(hoten);

if (strlen(hoten) == 0)

done = 1;

else

{

strcpy(danhsach[numrecords].hoten, hoten);

printf("

Lop : ");

gets(danhsach[numrecords].lop);

printf("

Diem toan : ");

scanf("%f", &diem);

danhsach[numrecords].diemtoan = diem;

printf("

Diem ly : ");

scanf("%f", &diem);

danhsach[numrecords].diemly = diem;

printf("

Diem hoa : ");

scanf("%f%*c", &diem);

danhsach[numrecords].diemhoa = diem;

numrecords++;

}

} while (!done);

}

void xoa()

{

int i, done = 0, found, dump[MAX];

char hoten[35], hotentmp[35];

while (!done)

{

if (numrecords != 0)

{

printf("

Ho ten hoc sinh can xoa (trong de thoat) : ");

gets(hoten);

if (strlen(hoten) == 0)

done = 1;

else

{

i = found = 0;

do {

strcpy(hotentmp,danhsach[i].hoten);

if (strcmp(strupr(hoten), strupr(hotentmp)) == 0)

dump[found++] = i;

i++;

} while (i<numrecords);

if (!found)

printf("

Khong tim thay hoc sinh co ten %s", hoten);

else

{

for (i=0; i<found; i++)

{

printf("

%3d %-35s %-7s %4.1f %4.1f %4.1f", i+1, danhsach[dump[i]].hoten,danhsach[dump[i]].lop,

danhsach[dump[i]].diemtoan, danhsach[dump[i]].diemly, danhsach[dump[i]].diemhoa);

}

printf("

Tim thay %d hoc sinh.", found);

printf("

Chon thu tu muon xoa (neu muon huy bo thi chon so khong nam trong pham vi): ");

scanf("%d", &i);

if (i >= 1 && i <= found)

{

for (found=dump[i-1]; found<numrecords-1; found++)

danhsach[found] = danhsach[found+1];

numrecords--;

printf("

Da huy");

}

else

printf("

Viec xoa bi huy bo.");

}

done = 1;

}

getch();

}

else

done = 1;

}

}

void sua()

{

int i, done = 0, found, dump[MAX];

char hoten[35], hotentmp[35];

float diem;

while (!done)

{

if (numrecords != 0)

{

printf("

Ho ten hoc sinh can sua (trong de thoat) : ");

gets(hoten);

if (strlen(hoten) == 0)

done = 1;

else

{

i = found = 0;

do {

strcpy(hotentmp,danhsach[i].hoten);

if (strcmp(strupr(hoten), strupr(hotentmp)) == 0)

dump[found++] = i;

i++;

} while (i<numrecords);

if (!found)

printf("

Khong tim thay hoc sinh co ten %s", hoten);

else

{

for (i=0; i<found; i++)

{

printf("

%3d %-35s %-7s %4.1f %4.1f %4.1f", i+1, danhsach[dump[i]].hoten,danhsach[dump[i]].lop,

danhsach[dump[i]].diemtoan, danhsach[dump[i]].diemly, danhsach[dump[i]].diemhoa);

}

printf("

Tim thay %d hoc sinh.", found);

printf("

Chon thu tu muon sua doi (neu muon huy bo thi chon so khong nam trong pham vi): ");

scanf("%d%*c", &i);

if (i >= 1 && i <= found)

{

printf("

%s

Ho ten : ", danhsach[dump[i-1]].hoten);

gets(danhsach[dump[i-1]].hoten);

printf("

%s

Lop : ", danhsach[dump[i-1]].lop);

gets(danhsach[dump[i-1]].lop);

printf("

%4.2f

Diem toan : ",danhsach[dump[i-1]].diemtoan);

scanf("%f", &diem);

danhsach[dump[i-1]].diemtoan = diem;

printf("

%4.2f

Diem ly : ", danhsach[dump[i-1]].diemly);

scanf("%f", &diem);

danhsach[dump[i-1]].diemly = diem;

printf("

%4.2f

Diem hoa : ", danhsach[dump[i-1]].diemhoa);

scanf("%f%*c", &diem);

danhsach[dump[i-1]].diemhoa = diem;

printf("

Da thay doi");

}

else

printf("

Viec thay doi bi huy bo.");

}

done = 1;

}

getch();

}

else

done = 1;

}

}

void lietke()

{

if (numrecords != 0)

{

printf("

+-----+------------------------------------+--------+------+------+------+");

printf("

| STT | H O V A T E N | L O P | TOAN | LY | HOA |");

printf("

+-----+------------------------------------+--------+------+------+------+");

for (i=0; i<numrecords; i++)

{

printf("

| %3d | ", i+1);

printf("%-35s| %-7s| %4.1f | %4.1f | %4.1f |", danhsach[i].hoten,danhsach[i].lop,

danhsach[i].diemtoan, danhsach[i].diemly, danhsach[i].diemhoa);

}

printf("

+-----+------------------------------------+--------+------+------+------+");

}

getch();

}

void getdata()

{

char c;

int start, nrec;

FILE *fp;

long curpos, length;

start = 0;

if (numrecords != 0)

{

printf("

Dang co du lieu trong bo nho. Co muon noi them vao khong?(C/K)");

c = toupper(getch());

if (c == 'C')

start = numrecords;

else

start = 0;

}

if ((fp = fopen(filename, "r")) == NULL)

printf("

Khong the mo tap tin %s", filename);

else

{

curpos = ftell(fp);

fseek(fp, 0L, SEEK_END);

length = ftell(fp);

fseek(fp, curpos, SEEK_SET);

nrec = length / sizeof(HOCSINH);

fread(&danhsach[start], sizeof(HOCSINH), nrec, fp);

fclose(fp);

printf("

Them vao %d records.", nrec);

numrecords = numrecords + nrec;

getch();

}

}

void putdata()

{

FILE *fp;

if ((fp = fopen(filename, "w+")) == NULL)

printf("

Khong thay ghi tap tin %s", filename);

else

{

fwrite(&danhsach[0], sizeof(HOCSINH), numrecords, fp);

fclose(fp);

printf("

Ghi %d records.", numrecords);

getch();

}

}

void main()

{

int chon, done = 0;

do {

chon = menu();

switch(chon)

{

case 1 : nhapmoi();

break;

case 2 : xoa();

break;

case 3 : sua();

break;

case 4 : lietke();

break;

case 5 : putdata();

break;

case 6 : getdata();

break;

case 0 : done = 1;

}

} while (!done);

}