Student Database project using Linked List.

#include<stdio.h>
#include<conio.h>
#define SIZE 10

struct Student
{
int rno;
char name[20];
float marks;
};
typedef struct Student Student;

void add(Student arr[], int pos)
{
float temp;
printf("\n Enter Student data ");
printf("\n Rno ");
scanf("%d", &arr[pos].rno);
printf("\n Name ");
flushall();
scanf("%s", arr[pos].name);
printf("\n Marks ");
scanf("%f", &temp);
arr[pos].marks = temp;

}//add

void dispAll(Student arr[], int tot)
{
int i;

printf("\n Rno    Name    Marks ");

for(i =0; i<tot; i++)
{
printf("\n %3d %10s %3.2f ", arr[i].rno, arr[i].name, arr[i].marks);
}
}//dispAll

int search(Student arr[], int tot, int r)
{//linear /sequentail search
int i;
for(i =0; i<tot; i++)
{
//x = strcmp(arr[i].name, n);
//if(x == 0)
//if(arr[i].marks ==m)
if(arr[i].rno == r)
{//match
return i; //index where found
}
}//for
return -1; //not found
}//search


void modify(Student arr[], int tot)
{
int r, x;
float temp;

printf("\n Enter rno of record to modify ");
scanf("%d", &r);

//look for the record
x = search(arr, tot, r);

if(x != -1)
{//modify
printf("\n Existing Data ");
printf("\n %3d %10s %3.2f ", arr[x].rno, arr[x].name, arr[x].marks);

printf("\n Enter new data ");

printf("\n Rno ");
scanf("%d", &arr[x].rno);
printf("\n Name ");
flushall();
scanf("%s", arr[x].name);
printf("\n Marks ");
scanf("%f", &temp);
arr[x].marks = temp;
}//if
else
{
printf("\n Record Not found");
}
}//Modify


int del(Student arr[], int tot)
{
int r, x, j;

printf("\n Enter rno of record to delete ");
scanf("%d", &r);

//look for the record
x = search(arr, tot, r);

if(x != -1)
{//delete
printf("\n Deleting ");
printf("\n %3d %10s %3.2f ", arr[x].rno, arr[x].name, arr[x].marks);

//slow shift method
for(j = x +1; j< tot; j++)
{
arr[j-1] = arr[j];
}
return 1;
}//if
else
{
printf("\n Record Not found");
return 0;
}
}//Modify

void sort(Student arr[], int tot)
{
Student temp;
int i, j;
for(i = tot-1; i >0; i--)
{
for(j =0 ; j< i;j++)
{
if(arr[j].rno > arr[j+1].rno)
{ //swap
temp = arr[j];
arr[j] = arr[j+1];
arr[j+1] = temp;
}
}//for(j
}//for(i
}//sort

void main()
{
Student sarr[SIZE];
int ch;
int indx= 0;
int r, flag;

do
{
printf("\n 1. Add Student ");
printf("\n 2. Modify Student ");
printf("\n 3. Delete Student ");
printf("\n 4. Search Student ");
printf("\n 5. Sort Student ");
printf("\n 6. Display All Students ");
printf("\n 7. Exit ");
printf("\n Enter choice ");

scanf("%d", &ch);

switch(ch)
{
case 1:
if(indx < SIZE)
{
add(sarr,indx);
indx++;
}
else
{
printf("\n Student Table Is FULL");
}
break;
case 2:
modify(sarr, indx);
break;
case 3:
flag = del(sarr, indx);
if(flag == 1)
{//deletion success
indx--;
}
break;
case 4://search
printf("\n Enter rno to search ");
scanf("%d", &r);
flag = search(sarr, indx, r);
if(flag != -1)
{
printf("\n Record found at index %d", flag);
printf("\n %3d %10s %3.2f ", sarr[flag].rno, sarr[flag].name, sarr[flag].marks);
}
else
{
printf("\n Record Not Found");
}
break;
case 5:
sort(sarr, indx);
break;
case 6:
dispAll(sarr, indx);
break;
}//switch

}while(ch != 7);
}