[Sidenote/JS] Using Recursion to Get All Possible Combinations
The definition of combination in mathematics is as follows:
In mathematics, a combination is a selection of items from a collection, such that the order of selection does not matter. (from Wikipedia)
In order to get all the possible selections, the following formula is used:
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The first part refers to all the combination that includes a certain value, and the latter part refers to all the combinations that does not include that value.