Definition:
1) Data structure is a particular way of
storing and organizing data in a computer so that it can be used efficiently.
2) Data structure is union of - set of
Domains, set of operations & set of axioms.
3) Data structure is a concept of C
language which reveals how to use Data Types, Functions, Dynamic Memory Allocation
in a program in such a way that programmer can write program that saves memory
and does more & complete processes.
Using data structure, a
program can allocate memory for variables, functions etc. and after its use
memory can be de-allocated. Also using DS, program can arrange data in such a
way that user can access and process in less time and less memory.
TYPES OF DS
1) Primitive: Basic, predefined, in built
DS. Ex- int, float, chars, logical data, pointers, etc.
2) Non primitive: Derived from
primitive, homogeneous & heterogeneous DS. Ex- struct, etc.
3) Static: DS for which allocate memory
at compile time.
4) Dynamic: DS for which allocate memory
at run time.
5) Linear: Data arranged in linear
pattern.
6) Non-linear: Data arranged in non-linear
pattern. Ex- tree, graph.
7) Persistent: data can be accessed but
can’t be modified. Ex- functions.
8) Ephemeral: data can be accessed and
modified. Ex- stack, queue.
For dynamic memory allocation, it
needs functions like malloc(), calloc(), realloc(), free() and prototype of
these functions is defined in stdlib.h. Also prototype of exit() is defined in
stdlib.h.
One program of Single Link List-
#include<stdio.h>
#include<stdlib.h>
typedef struct node
{
int
data;
struct
node *next;
}NODE;
NODE *create(NODE *);
void display(NODE *);
int main()
{
NODE
*root;
int
ch;
root=NULL;
while(1)
{ printf("\n\n---->
SLL OPR <---- \
\n
1 Enter SLL values \
\n
2 Print values \
\n
3 Exit \
\n
Enter choise = ");
scanf("%d",&ch);
switch(ch)
{
case
1: root=create(root);
break;
case
2: display(root);
break;
case
3: exit(0);
}
}
return 0;
}
NODE *create(NODE *root)
{
NODE
*ptr;
printf("\n\n
CREATE MENU");
printf("\n\n
Enter value - ");
if(root==NULL)
{
root=(NODE
*)malloc(sizeof(NODE));
scanf("%d",&root->data);
root->next=NULL;
}
else
{
for(ptr=root;
ptr->next!=NULL; ptr=ptr->next);
ptr->next=(NODE
*)malloc(sizeof(NODE));
scanf("%d",&ptr->next->data);
ptr->next->next=NULL;
}
return (root);
}
void display(NODE *root)
{
NODE
*ptr;
printf("\n\n---->
DISPLAY MENU <----\n\n");
for(ptr=root;
ptr!=NULL; ptr=ptr->next)
printf("\t%d",ptr->data);
}
Rest of program for modification,
deletion, sorting is as per given in syllabus and written in TC.
This is
