D.Y.PATIL TECHNICAL CAMPUS, TALSANDE
FACULTY OF ENGINEERING & FACULTY OF
MANAGEMENT
(Polytechnic)
A Microproject Report On
“Information About Stack Data Structure”
Submitted By
Enrollement No.
Name Of Student
2212200044
Nikita Prakash Khot
2212200045
Supriya Sudarshan Bedkale
2212200046
Shruti Ashok Patil
Guided By
Ms. Gurav.P.S
D.Y.PATIL TECHNICAL CAMPUS, TALSANDE FACULTY OF
ENGINEERING & FACULTY OF MANAGEMENT
(Polytechnic)
DEPARTMENT OF COMPUTER ENGINEERING
SEMESTER III
CERTIFICATE
This is Certify that student
of Computer Engineering has
successfully completed the project term work
“Report on Stack
Data Structure.” in partial fulfillment of the Diploma of Engineering
in
Computer as laid down during academic year 2023-24
Roll No.
Name of Student
2219
Khot Nikita Prakash
2220
Bedkale Supriya Sudarshan
2221
Patil Shruti Ashok
Ms. Gurav.P.S
Project Guide
Mr. Kumbhar R. S.
HoD
Dr. S. R. Pawaskar
Principal
Date –
Exam Seat No.
/
– Talsande
/202 Place
INDEX
Sr.
No.
1
Title
Introduction
Page No.
4
2
Information about Stack
5-7
3
Real Time Example of Stack Data Structure
7
4
5
Application of Stack
Operation on Stack
8-9
10-14
6
Stack implementation using ‘C’ Program
15-16
7
Output of code
17-18
8
Conclusion
19
9
References
20
Information About Stack Data structure.
Introduction
A Stack is a linear data structure that follows the LIFO (Last-In-First-Out) principle. Stack
has one end, whereas the Queue has two ends (front and rear). It contains only one pointer top
pointer pointing to the topmost element of the stack. Whenever an element is added in the stack,
it is added on the top of the stack, and the element can be deleted only from the stack. In other
words, a stack can be defined as a container in which insertion and deletion can be done from the
one end known as the top of the stack.
Stack works on the LIFO pattern. As we can observe in the below figure there are five memory
blocks in the stack; therefore, the size of the stack is 5.
Suppose we want to store the elements in a stack and let's assume that stack is empty. We have
taken the stack of size 5 as shown below in which we are pushing the elements one by one until
the stack becomes full.
Since our stack is full as the size of the stack is 5. In the above cases, we can observe that it goes
from the top to the bottom when we were entering the new element in the stack. The stack gets
filled up from the bottom to the top.
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Information About Stack Data structure.
A Stack is a linear data structure that follows the LIFO (Last-In-First-Out) principle. Stack
has one end, whereas the Queue has two ends (front and rear). It contains only one pointer top
pointer pointing to the topmost element of the stack. Whenever an element is added in the stack,
it is added on the top of the stack, and the element can be deleted only from the stack. In other
words, a stack can be defined as a container in which insertion and deletion can be done from the
one end known as the top of the stack.
Some key points related to stack :
o
It is called as stack because it behaves like a real-world stack, piles of books, etc.
o
A Stack is an abstract data type with a pre-defined capacity, which means that it can store
the elements of a limited size.
o
It is a data structure that follows some order to insert and delete the elements, and that
order can be LIFO or FILO.
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Information About Stack Data structure.
Working of Stack
Stack works on the LIFO pattern. As we can observe in the below figure there are five memory
blocks in the stack; therefore, the size of the stack is 5.
Suppose we want to store the elements in a stack and let's assume that stack is empty. We have
taken the stack of size 5 as shown below in which we are pushing the elements one by one until
the stack becomes full.
Since our stack is full as the size of the stack is 5. In the above cases, we can observe that it goes
from the top to the bottom when we were entering the new element in the stack. The stack gets
filled up from the bottom to the top.
When we perform the delete operation on the stack, there is only one way for entry and exit as
the other end is closed. It follows the LIFO pattern, which means that the value entered first will
be removed last. In the above case, the value 5 is entered first, so it will be removed only after
the deletion of all the other elements.
Standard Stack Operations:
The following are some common operations implemented on the stack:
o
push(): When we insert an element in a stack then the operation is known as a push. If
the stack is full then the overflow condition occurs.
o
pop(): When we delete an element from the stack, the operation is known as a pop. If the
stack is empty means that no element exists in the stack, this state is known as an
underflow state.
o
isEmpty(): It determines whether the stack is empty or not.
o
isFull(): It determines whether the stack is full or not.' o
peek(): It returns the element
at the given position.
o
count(): It returns the total number of elements available in a stack.
o
change(): It changes the element at the given position. o display(): It prints all the
elements available in the stack.
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Information About Stack Data structure.
Real Time Examples of Stack Data Structure
Stack is a linear data structure which follows a particular order in which the operations are
performed. The order may be LIFO(Last In First Out) or FILO(First In Last Out).
There are many real-life examples of a stack. Consider an example of plates stacked over
one another in the canteen. The plate which is at the top is the first one to be removed, i.e.
the plate which has been placed at the bottommost position remains in the stack for the
longest period of time. So, it can be simply seen to follow LIFO(Last In First
Out)/FILO(First In Last Out) order.
1)
2)
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Information About Stack Data structure.
Applications of Stack
The following are the applications of the stack:
o
Balancing of symbols: Stack is used for balancing a symbol. For example, we have the
following program:
int main()
{
cout<<"Hello";
cout<<"javaTpoint";
}
As we know, each program has an opening and closing braces; when the opening braces
come, we push the braces in a stack, and when the closing braces appear, we pop the
opening braces from the stack. Therefore, the net value comes out to be zero. If any
symbol is left in the stack, it means that some syntax occurs in a program.
o
String reversal: Stack is also used for reversing a string. For example, we want to
reverse a "javaTpoint" string, so we can achieve this with the help of a stack. First, we
push all the characters of the string in a stack until we reach the null character. After
pushing all the characters, we start taking out the character one by one until we reach the
bottom of the stack.
o
UNDO/REDO: It can also be used for performing UNDO/REDO operations. For
example, we have an editor in which we write 'a', then 'b', and then 'c'; therefore, the text
written in an editor is abc. So, there are three states, a, ab, and abc, which are stored in a
stack. There would be two stacks in which one stack shows UNDO state, and the other
shows REDO state.
If we want to perform UNDO operation, and want to achieve 'ab' state, then we
implement pop operation.
o
Recursion: The recursion means that the function is calling itself again. To maintain the
previous states, the compiler creates a system stack in which all the previous records of
the function are maintained.
o
DFS(Depth First Search): This search is implemented on a Graph, and Graph uses the
stack data structure.
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Information About Stack Data structure.
o
Backtracking: Suppose we have to create a path to solve a maze problem. If we are
moving in a particular path, and we realize that we come on the wrong way. In order to
come at the beginning of the path to create a new path, we have to use the stack data
structure.
o
Expression conversion: Stack can also be used for expression conversion. This is one of
the most important applications of stack. The list of the expression conversion is given
below:
1. Infix to prefix
2. Infix to postfix
3. Prefix to infix
4. Prefix to postfix
5. Postfix to infix
o
Memory management: The stack manages the memory. The memory is assigned in the
contiguous memory blocks. The memory is known as stack memory as all the variables
are assigned in a function call stack memory. The memory size assigned to the program
is known to the compiler. When the function is created, all its variables are assigned in
the stack memory. When the function completed its execution, all the variables assigned
in the stack are released.
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Information About Stack Data structure.
Operations on Stack
Stack operations may involve initializing the stack, using it and then de-initializing it. Apart
from these basic stuffs, a stack is used for the following two primary operations −
•
push() − Pushing (storing) an element on the stack.
•
pop() − Removing (accessing) an element from the stack.
When data is PUSHed onto stack.
To use a stack efficiently, we need to check the status of stack as well. For the same purpose,
the following functionality is added to stacks −
•
peek() − get the top data element of the stack, without removing it.
•
isFull() − check if stack is full.
•
isEmpty() − check if stack is empty.
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Information About Stack Data structure.
1) isfull():
Algorithm of isfull() function −
begin procedure isfull
if top
equals to MAXSIZE
return
true else
return false endif
end procedure;
Implementation of isfull() function in C programming language −
Example
int isfull() {
if(top == MAXSIZE)
return 1;
else
return 0;
}
2) isempty():
Algorithm of isempty() function −
begin procedure isempty
if top less than
1
else
false
return true
return
endif end
procedure
Implementation of isempty() function in C programming language is slightly different.
We initialize top at -1, as the index in array starts from 0. So we check if the top is
below zero or -1 to determine if the stack is empty. Here's the code −
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Information About Stack Data structure.
Example
bool isempty()
{
if(top == -1)
return true;
else
return
false;
}
3) Push():
The process of putting a new data element onto stack is known as a Push Operation.
Push operation involves a series of steps −
•
Step 1 − Checks if the stack is full.
•
Step 2 − If the stack is full, produces an error and exit.
•
Step 3 − If the stack is not full, increments top to point next empty space.
•
Step 4 − Adds data element to the stack location, where top is pointing.
•
Step 5 − Returns success.
If the linked list is used to implement the stack, then in step 3, we need to allocate space
dynamically.
Algorithm for PUSH Operation
A simple algorithm for Push operation can be derived as follows − begin
procedure push: stack, data
if stack is full
return null endif
top ← top + 1
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Information About Stack Data structure.
stack[top] ← data
end procedure
Implementation of this algorithm in C, is very easy. See the following code −
Example
void push(int data)
{
if(!isFull
()
{
top = top + 1;
stack[top] = data;
}
else
{
printf("Could not insert data, Stack is full.\n");
}
}
4) Pop Operation
Accessing the content while removing it from the stack, is known as a Pop Operation.
In an array implementation of pop() operation, the data element is not actually removed,
instead top is decremented to a lower position in the stack to point to the next value.
But in linked-list implementation, pop() actually removes data element and deallocates
memory space.
A Pop operation may involve the following steps −
•
Step 1 − Checks if the stack is empty.
•
Step 2 − If the stack is empty, produces an error and exit.
•
Step 3 − If the stack is not empty, accesses the data element at which top is pointing.
•
Step 4 − Decreases the value of top by 1.
•
Step 5 − Returns success.
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Information About Stack Data structure.
Algorithm for Pop Operation
A simple algorithm for Pop operation can be derived as follows −
begin procedure pop: stack
if stack is empty
return null endif
data ← stack[top]
top ← top - 1
return data
end procedure
Implementation of this algorithm in C, is as follows −
Example
int pop(int data) {
if(!isempty())
{
data =
stack[top];
top - 1;
top =
return
data; } else {
printf("Could not retrieve data, Stack is empty.\n");
}
}
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Information About Stack Data structure.
Stack implementation using ‘C’ Program
#include<stdio.h>
break;
#include<process.h>
case 4: empty();
#include<stdlib.h>
break;
#define MAX 5 //Maximum number
case 5: full();
of elements that can be stored
break;
int top=-1,stack[MAX];
case 6:exit(0);
void push();
default: printf("\nWrong Choice!!");
void pop();
}
void display();
}
void empty();
}
void full();
void push()
void main()
{
{
int val;
int ch;
if(top==MAX-1)
clrscr();
{
while(1) //infinite loop, will end when
printf("\nStack is full!!");
choice will be 6
}
{
else {
printf("\n*** Stack
printf("\nEnter element to push:");
Menu***");
scanf("%d",&val);
printf("\n\n1.Push\n2.Pop\n3.Display\n4.Chec
top=top+1;
k Stack is empty or not?\n5.Check Stack is full
stack[top]=val;
or not?\n6.Exit"); printf("\n\nEnter your
}
choice(1-6):"); scanf("%d",&ch); switch(ch)
}
{
Case1:push
void pop()
{
break;
if(top == -1)
case 2:pop();
{
break;
printf("\nStack is empty!!");
}
Case 3:display()
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Information About Stack Data structure.
else {
{
printf("\nDeleted element
printf("\nStack is full!!");
is %d",stack[top]);
}
top=top-1;
else
}
{
}
printf("\nStack is not Full!!");
Void display
}
{
}
int i;
if(top==-1)
{
printf("\nStack is empty!!");
}
Else
{
printf("\nStack is\n");
for(i=top;i>=0;--i)
printf("%d\n",stack[i]);
}
}
void empty()
{
if(top==-1)
{
printf("\nStack is empty!!");
}
Else
{
printf("\nstack is not Empty!!");
}
}
void full()
{
if(top==MAX-1)
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Information About Stack Data structure.
Output of code
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Information About Stack Data structure.
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Information About Stack Data structure.
Conclusion
A real-world stack allows operations at one end only. For example, we can place or remove a
card or plate from the top of the stack only. Likewise, Stack ADT allows all data operations
at one end only. At any given time, we can only access the top element of a stack.
This feature makes it LIFO data structure. LIFO stands for Last-in-first-out. Here, the
element which is placed (inserted or added) last, is accessed first. In stack terminology,
insertion operation is called PUSH operation and removal operation is called POP operation.
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Information About Stack Data structure.
References
1. https://www.google.com/
2. https://www.simplilearn.com/tutorials/data-structuretutorial/stacksindatastructures#:~:text=Stacks%20in%20Data%20Structures%20is,
data %20structure%2C%20that%20is%20top.
3. https://www.geeksforgeeks.org/stack-data-structure/
4. https://www.javatpoint.com/data-structure-stack
5. https://www.w3schools.in/datastructures/stack#:~:text=A%20stack
%20is%20a%20linear,Infix
6. Data structure using c, Tech-max publication.
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