Are the Books in Order?

The librarian numbered every book, and the shelf should go up as you read left to right. 📚

You get the shelf as a list of nums. Print in order if each number is at least as big as the one before it, otherwise mixed up.

Example:

Input: nums = [3, 7, 7, 12] Output: in order

Each number is at least as big as the one before it (3≤7, 7≤7, 7≤12), so nothing breaks the flag — print in order.