The document defines key concepts related to data structures and algorithms including data structure, data, data processing, information, linear and non-linear data structures, algorithms, time and space complexity, and provides examples of linked lists, stacks, and the push and pop operations on stacks. It also includes C code for implementing a stack using a linked list with functions for push, pop and display operations.

1.  What is data structure?
Ans: Is the way of sorting and organizing data in computer memory or even
disk storage
 What is Data?
Ans: is row facts about people place or entities(1).
 What is data processing?
Ans: Is the way of putting data in its type in the memory or disk spaces.
 What is information?
Ans: is the output of data been processed.Oris the useful dat.
 Types of data structure
 -Linear Data Structure : Is the way of organizing data sequenced order In
the memory. Or sequenced data.
 -Non-Linear Data Structure: is non-sequenced data.
 Examples of linear and non-linear data structures
1: Linear “Arrays, Linked List, Queue”
2: Non-linear “Stark, tress, Graphs”
Chapter 2:
 An algorithm :is a well-defined computational method, which takes some
value(s) as input and produces somevalue(s) as output. In other words, an
algorithm is a sequence of computational steps that transforms input(s) into
output(s).
 Problem Definition: Sort given n numbers by non-descending order by
using insertion sort.
 Space Complexity: The Space complexity of an algorithm is the amount of
main memory needed to run the program till completion.
 Time Complexity: The Time complexity of an algorithm is the amount of
computer time it needs to run the program till completion.
 Linked list: is a linear dynamic data structure.
 Singly linked list: is a linked list which is a linear list of some nodes
containing homogeneous elements
 Doubly linked list: is a linked list which is a linear list of some nodes
containing homogeneous elements.
 Circular linked list: is a linked list similar with the singly linked list. The
only difference between the circular linked list and the singly linked list
 Stack : is a special type of data structure where elements are inserted from one
end and elements are deleted from the same end.
 Push : Data is added to the stack using the Push operation.
 Pop : Data is removed using the Pop operation

2.  Push operation : The procedure of inserting a new element to the top of the stack
is known as push operation.
 Programming
 #include<stdio.h>
 #include<conio.h>
 #include<malloc.h>
 #include<stdlib.h>
 void push(); //push() function declaration
 void pop(); //pop() function declaration
 void display(); //display() function declaration
 struct node
 {
 int data;
 struct node *next;
 };
 struct node *top=NULL;
 void main()
 {
 int choice;
 clrscr();
 while(1)
 {
 printf("n1.Push");
 printf("n2.Pop");
 printf("n3.Display");
 printf("n4.Quit");
 printf("nEnter your choice:");
 scanf("%d",&choice);
 switch(choice)
 {
 case 1: push();
 break;
 case 2: pop();
 break;
 case 3: display();
 break;
 case 4: exit(1);
 default:printf("Invalid Choicen");
 }//end of switch
 } //end of while loop
 }//end of main fuction

3.  void push()
 {
 struct node *ptr;
 int item;
 ptr=(struct node *)malloc(sizeof(struct node));
 printf("Enter a value to be pushed onto the stack: ");
 scanf("%d",&item);
 ptr->data=item;
 ptr->next=top;
 top=ptr;
 }//end of push fuction
 void pop()
 {
 struct node *ptr,*next;
 if(top==NULL)
 printf("nStack is Empty");
 else
 {
 ptr=top;
 printf("nPopped element is : %dn",ptr->data);
 top=top->next;
 free(ptr);
 }
 }//end of pop function definition
 void display()
 {
 struct node *p;
 p=top;
 if(top==NULL)
 printf("nStack is emptyn");
 else
 {
 printf("nStack elements:n");
 while(p!=NULL)
 {
 printf("%dn",p->data);
 p=p->next;
 }
 }
 } //end of display function