Guess the path

Guess the Path is a puzzle game for the smartest of you.
So yes, the first levels are quite simple and you will tell yourself that it is a game for children ... but not at all, try the more difficult levels ... you will understand that this game is not for put in all hands ... or rather not to put in all brains.
You must thus connect all the boxes together and fill in the grid completely. It's simple but it becomes quite difficult as the size of the grid increases.

The principle of the game is very simple, you must fill the grid with numbers ranging from 1 to X. The numbers must follow each other on the grid, that is to say that for example the box number 2 must be located next to the box 1, and box 3 must be located next to box 2, etc ...