public/subjects/crossword/README.md

## crossword

### Instructions

Create the function `crosswordSolver` that is able to solve an empty crossword puzzle. The function must be submitted in a file named `crosswordSolver.js`.

The function takes two arguments:
1. an empty puzzle, passed as a string and
2. a list of words to fill in the puzzle (no double words allowed)

The function must print on the console a string representing the puzzle filled with the input words.

The empty puzzle will be a string with the following rules:
- each character will be either a number, a `.` or a `\n`;
- a number represents the number of words starting from the specific position and a `.` represents a space that does not need to be filled. 

If the puzzle or list of words provided as inputs does not guarantee a unique solution, or any other conditions stated above are not met, the function must print `'Error'`. 

### Examples

```js

const emptyPuzzle = 
`2001
0..0
1000
0..0`
const words = ['casa', 'alan', 'ciao', 'anta']

crosswordSolver(emptyPuzzle, words)

/* output:
`casa
i..l
anta
o..n`
*/
```