You are given a phone number as a string number. The string number consists of digits, spaces ' ', and dashes '-'.

Reformat the phone number by applying the following steps:

1. Remove all spaces and dashes.

2. Group the digits from left to right into blocks of length $3$ until $4$ or fewer digits remain.

3. For the remaining digits:
   • If $2$ digits remain, place them in a single block of length $2$.
   • If $3$ digits remain, place them in a single block of length $3$.
   • If $4$ digits remain, split them into two blocks of length $2$ each.

Join all blocks using the separator '-' and return the reformatted phone number.

Constraints:

• $2 \le$ number.length $\le 100$

• number consists of digits and the characters '-' and ' '.

• There are at least $2$ digits in number.

Now, let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.