rpn-infix-postfix/README.md

RPN infix to posfix

# RPN 
<p align="center">
  <img src = 'https://upload.wikimedia.org/wikipedia/commons/d/d2/Jan_%C5%81ukasiewicz.jpg' width = '400' height = '400'/>
  <br>Jan Łukasiewicz <i>(Inventor of RPN)</i>
</p>

## Infix to postfix

> Reverse Polish notation (RPN), also known as Polish postfix notation or simply postfix notation, is a mathematical notation in which operators follow their operands, in contrast to Polish notation (PN), in which operators precede their operands. It does not need any parentheses as long as each operator has a fixed number of operands. The description "Polish" refers to the nationality of logician Jan Łukasiewicz, who invented Polish notation in 1924  &nbsp;&nbsp;&nbsp;&nbsp;-*Wikipedia*

<br>

## Npm
### Downloading
```  $npm i rpn-infix-postfix ```

### Usage
```javascript
const { 
  infixToPostfix,
  postfixSolver,
  solve,
  Stack }  = require('rpn-infix-postfix');

console.log(solve('1 + 2 * 9' )); // result => 19
console.log(
  infixToPostfix('1*(4-2)', new Stack(100)).join('')
); // result => 142-*
```

## Downloading (via git)
```
git clone https://github.com/SC0d3r/RPN-infix-to-postfix.git RPN
```
## cli Usage
#### after cloning go to directory and then run the following command
```javascript
$node index.js '1* ( 2 + 3)'
 
    > 5 [result]
```
### only postfix version

```javascript
$node index.js '1* ( 2 + 3)' -postfix
 
   > 123+* [result]
```

## Test
### run tests with
``` $npm test ```