Write applications of Stack.

The applications of Stack include:

1. Reversing a Word/Line — This can be accomplished by pushing each character on to a Stack as it is read. When the line is finished, characters are popped off the Stack and they will come off in the reverse order.
2. Evaluation of Arithmetic Expressions — Stack is used to evaluate these arithmetic expressions on the basis of operator precedence.
3. Processing Function Calls — The compilers use Stacks to store the previous state of a program when a function is called or during recursion.
4. Backtracking — Backtracking is a form of recursion which involves choosing only one option out of the possibilities. Backtracking is used in a large number of puzzles like Sudoku and in optimization problems such as Knapsack.
5. Undo Mechanism in Text Editors — This operation is accomplished by keeping all text changes in a Stack.