## Topic : Stack (Key Note and Questions)

** ****Key Note:**

*Stack is a linear data structure that follows LIFO principles.**LIFO stands for Last In First Out**We can implement stack using linked list and array.**Some Application of Data Structure are Infix to Postfix conversion, Infix to Prefix conversion, Postfix and prefix evaluation etc.*

### Questions

- What is stack? Explain with suitable example with all its application.
- Implement stack with singly linked list.
- What is push and pop operation of stack? Write the algorithm for push and pop operation.
- Write a program in c for array implementation of stack.
- Write a program in c for linked list implementation of stack.
- What is infix, prefix and postfix expression? Explain with example.
- Write down an algorithm to evaluate the infix expression.
- Write down an algorithm to evaluate the postfix expression.
- Write down an algorithm to evaluate the Prefix expression.
- Convert following infix expression into postfix expression A+(B*C+D)/E
- Write an algorithm to convert a postfix expression into an infix expression. Consider the following arithmetic expression in postfix notation: 752+*415-/-
- Write an algorithm to convert Infix expression to Prefix. Convert this expression into prefix
- What is recursion? Write its principle. Explain with the help of example.
- Explain the types of recursion.
- Explain Tower of Hanoi with example.
- Write the recursive algorithm for solving the problem of Tower of Hanoi and also explain its complexity. Illustrate the solution for four disks and three pegs.

## Topic : Queue (Key Note and Questions)

** ****Key Note:**

*Queue is a linear data structure that follows FIFO principles.**FIFO stands for First In First Out.**Queue can be implemented using Array and Linked List.**Application of Queue is, Queue is helpful in CPU scheduling, Disk Scheduling, Handling of interrupts in real-time systems etc*