The document discusses various applications of stacks including: 1) Reversing strings by pushing characters onto a stack and popping them off in reverse order. 2) Calculator operations using postfix notation and a stack. 3) Recursive functions using a stack to store previous function calls and variables. 4) Determining if a word is a palindrome by pushing characters onto a stack and comparing to the popped off characters. Code examples are provided for reversing strings, recursive summation, and determining palindromes using stacks.

2.  STACK

3. Introduction
Application
Conclusion

4. Khadijatul Kobra Shila
I.D:142-15-3616

5. A stack is a data structure that stores data in
such a way that the last piece of data stored, is
the first one retrieved.
LAST IN FIRST OUT =LIFO
To get the bottom plate out,
you must first remove all
the plates above.
Example of stack

6. All these applications follow the LIFO logic.
REAL LIFE: Stacks are present everyday life.From
the books in a library, to the blank sheets of paper in a
printer tray systems are used STACK to complete their
acts.
#PILES OF BOOKS:
A book is added on top of a pile
of books, while removing a book
from a pile also takes the book on
top of a pile in everywhere.

7. #VISULAZE
STAGE:
TOP
Pile of Books

8. #SOURCE CODE:
void push(int *top, element
item)
{
/* add an item to the global
stack */
if (*top >=
MAX_STACK_SIZE-1) {
stack_full( );
return;
}
stack[++*top] = item;
}
Push
element pop(int *top)
{
/* return the top element
from the stack */
if (*top == -1)
return
stack_empty( );
/* returns and error key */
return stack[(*top)--];
}
Pop

9. Rahul Debnath
ID: 142-15-3484

10. RLATEDTO COMPUTER SCIENCE:
Below are a few applications of stacks in
computing.
#REVERSING STRING:
A simple application of stack is reversing strings.
To reverse a string , the characters of string are pushed onto
the stack one by one as the string is read from left to right.
To reverse the string ‘REVERSE’ the string is read
from left to right and its characters are pushed.LIKE:

11. E
S
R
E
V
E
R
REVERSE ESREVER
String is Reverse String
Stack
#VISULAZE
STAGE:

12. #define MAX 20
int top = -1;
char stack[MAX];
char pop();
void push(char);
main()
{
char str[20];
int i;
printf(“Enter the string : ” );
gets(str);
for(i=0;i<strlen(str);i++)
push(str[i]);
for(i=0;i<strlen(str);i++)
str[i]=pop();
printf(“Reversed string is : “);
puts(str);
void push(char item){
if(top == (MAX-1))
{
printf(“Stack Overflown”);
return;
}
stack[++top] =item;
}/*End of push()*/
char pop(){
if(top == -1)
{
printf(“Stack Underflown”);
exit(1);
}
return stack[top–];
}

13. Abu Zafor Tomal
I.D:142-15-3816

14. #Calculator Methodology:
Every arithmetic operation in calculator follow
the stack postfix notation.
*
+
9 6 39+6*3
Equation
Postfix string
Stack

15. Create Stack
While(not end of postfix notation){
ch = getch()
if(ch is operand)
push(ch)
else{
operand1 = pop()
operand2 = pop()
result = operand2 ch operand1
push(result)
}
}
Result = pop()

16. Abul Hasnath Limon
ID:142-15-3532

17. #Function ( recursive ):
A very good example of stack is Function.
Summation of positive integer can be implemented by
recursive function and the functions are stored in a stack to
maintain the sequence of summation.
When a function is called within a function then the previous
function is stored in a stack with it’s local variables.
Summation of positive numbers with code example:

18. #include <stdio.h>
int sum(int n);
int main(){
int num,add;
printf("Enter a positive integer:n");
scanf("%d",&num);
add=sum(num);
printf("sum=%d",add);
}
int sum(int n){
if(n==0)
return n;
else
return n+sum(n-1);
/*self call to function sum() */
}
Enter a positive integer: 5
15
Output

19. For better visualization of recursion in
this example:
sum(5)
=5+sum(4)
=5+4+sum(3)
=5+4+3+sum(2)
=5+4+3+2+sum(1)
=5+4+3+2+1+sum(0)
=5+4+3+2+1+0
=5+4+3+2+1
=5+4+3+3
=5+4+6
=5+10
=15
Sum(1)
Sum(2)
Sum(3)
Sum(4)
Sum(5)
All functions are pushed in stack

20. Umme Habiba
ID:142-15-3677

21. Implementation : Palindrome
A palindrome is a word, phrase, number, or other sequence of
Characters which reads the same backward or forward.
Allowances may be made for adjustments to capital letters,
punctuation, and word dividers.
Suppose :
ABCDCBA is a palindrome
FGHHGF is a palindrome
ASDFASDF is not a palindrome

22. C
I
V
I
C
C
I
V
I
C
PUSH POP
Stack Stack
Palindrome
Word
After pushing and popping, CIVIC word remain unchanged
#VISULAZE
STAGE:

23. Source code:
char stk[50];
int top=-1;
void push(char c){
top++;
stk[top]=c;
}
char pop(){
char c;
c=stk[top];
top–;
return c;
}
void main(){
char in[30],b[30];
int i;
printf(“nn ENTER UR STRINGt”);
gets(in);
for(i=0;in[i]!=‘’;i++){
push(in[i]);
}
i=0;
while(top!=-1){
b[i]=pop();
i++;
}
b[i]=‘’;
if(strcmp(in,b)==0){
printf (“n STRING is
PALLINDROME”);
}
else{
printf (“n STRING IS NOT
PALLNDROME”);
}
}

24. ThankYou