Bsc CSIT Semester 3 – Data Structure and Algorithms – Unit 2: Stack (4 Hrs.)

Question 1

Explain push and pop operations of stack. What are different applications of stack?

Marks: 5

Year: 2080 Final TU

Stack (Definition) A Stack is a linear data structure that follows the LIFO (Last In, First Out) principle. The element inserted last is removed first. Examples: - Stack of plates - Undo/Redo op

Question 2

Convert the infix expression A+(((B-C)(D-E)+F)/G)$(H-I) into post expression using stack.

Marks: 5

Year: 2081 Final TU

1. Definition Infix Expression An infix expression is an expression in which the operator is written between operands. Example: A + B Postfix Expression A postfix expression (Reverse Polish No

Question 3

How recursive algorithm uses stack to store intermediate results? Illustrate with an example. Convert the infix expression A+B-(CD/E+F)-GH into postfix expression using stack.

Marks: 10

Year: 2079 Final TU

Part A: Use of Stack in Recursive Algorithms Definition of Recursion A recursive algorithm is an algorithm that solves a problem by calling itself with a smaller subproblem until a base condition is

Question 4

Evaluate the postfix expression 574-8/4+ using stack.

Marks: 5

Year: 2079 Final TU

1. Definition A postfix expression (Reverse Polish Notation) is an expression in which operators come after operands. It is evaluated using a stack by scanning the expression from left to right. ---

Question 5

Evaluate the expression ABCD-x+ using stack where A=5, B=4, C=3 and D=7

Marks: 5

Year: 2078 Final TU

Step 1: Replace variables with values ABCD-x+ → 5 4 3 7 - x + (Assuming x means multiplication in this context; if it's subtraction, replace accordingly.) Here, let's consider x as multiplication .

Question 6

What is stack? What are the different applications of stack? Explain stack operations with example.

Marks: 10

Year: 2077 Final TU

1. Definition of Stack A Stack is a linear data structure that follows the principle of LIFO (Last In, First Out). - The element inserted last is removed first. - All insertions and deletions take p

Question 7

Explain algorithm for evaluation of postfix expression using stack

Marks: 5

Year: 2077 Final TU

Algorithm to Evaluate Postfix Expression 1. Definition A postfix expression (also called Reverse Polish Notation) is an expression in which the operator comes after the operands. Example: 2354+9- A