# reverse-polish-notation

Created by [@Divlo](https://github.com/Divlo) on 29 September 2020.

## Instructions

Your job is to create a calculator which evaluates expressions in Reverse Polish notation (a mathematical notation in which operators follow their operands. It does not need any parentheses as long as each operator has a fixed number of operands).

For example expression 5 1 2 + 4 / + 3 - (which is equivalent to 5 + ((1 + 2) / 4) - 3 in normal notation) should evaluate to 14.

For your convenience, the input is formatted such that a space is provided between every token.

Empty expression should evaluate to 0.

Valid operations are +, -, \*, /.

You may assume that there won't be exceptional situations (like stack underflow or division by zero).

## Source

- [Reverse polish notation - Codewars](https://www.codewars.com/kata/52f78966747862fc9a0009ae)

## Examples

See the `test` folder for examples of input/output.