CREATE STUDENTS DATABASE USING STRUCTURE AND PERFORM OPERATIONS ACCEPT,SEARCH ,DISPLAY,DELETE&MODIFY.

  STRUCTURE:

              The structure is a user-defined data type in C language which allows us to combine data of different types together. Structure helps to construct a complex data type that is more meaningful. It is somewhat similar to an Array, but an array holds data of a similar type only.

                                            PROGRAM  ON STRUCTURE

#include<stdio.h>
#include<conio.h>
struct student
{
  int rollno;
  char name[10];
}s[20];
void accept(struct student s[20],int n);
void display(struct student s[20],int n);
void search(struct student s[20],int n);
void modify(struct student s[20],int n);
void dele(struct student s[20],int n);
void main()
{
   int n,a1,a=0;
   clrscr();
   printf("Enter no students");
   scanf("%d",&n);
 while(a!=4)
 {
   printf("Enter 1 to accept data\nEnter 2 to display data\nEnter 3 to search record\nEnter 4 for modification\nEnter 5 for delete\n ");
   scanf("%d",&a1);


  switch(a1)
   {
     case 1:accept(s,n);
     break;
     case 2:display(s,n);
     break;
     case 3:search(s,n);
     break;
     case 4:modify(s,n);
     break;
     case 5:dele(s,n);
     break;
   }
  a++;
 }
getch();
}

void accept(struct student s[20],int n)
 {
   int i;
   for(i=0;i<n;i++)
     {
       printf("Enter rollno and name");
       scanf("%d%s",&s[i].rollno,&s[i].name);
     }

 }

void display(struct student s[20],int n)
   {  int i;
      for(i=0;i<n;i++)
     {
       printf(" rollno and name are\n");
       printf("%2d%2s\n",s[i].rollno,s[i].name);

     }


   }

   void search(struct student s[20],int n)
      {
  int i,flag,na;
  printf("Enter rollno to be searched\n");
  scanf("%d",&na);
  for(i=0;i<n;i++)
    {
      flag=0;
      if(s[i].rollno==na)
        { flag=1;
   break;
  }
    }
  if(flag==1)
  printf(" present\n");
  else
  printf(" not present");

      }
   void modify(struct student s[20],int n)
      {
 int i,flag,na;
  printf("Enter rollno to be searched");
  scanf("%d",&na);
    for(i=0;i<n;i++)
      {
        flag=0;
  if(s[i].rollno==na)
     {
      flag=1;
     }
      }
   if(flag==1)
    {
      printf("Enter rollno and name");
      scanf("%d%s",&s[na].rollno,&s[na].name);
      printf("%2d%2s\n",s[na].rollno,s[na].name);
    }
   else
   printf("not possible");
      }
   void dele(struct student s[20],int n)
      {
  int i,flag,na;
  printf("Enter rollno to be searched");
  scanf("%d",&na);
    for(i=0;i<n;i++)
      {
        flag=0;
  if(s[i].rollno==na)
     {
      flag=1;
     }

    if(flag==1)
      {

       s[na].rollno=s[++na].rollno;
       na=--na;
       s[na].name=s[++na].name;



      }
      }