javascript - Choosing a value from each of n identical arrays, get all combinations -

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let's have 3 identical arrays, each looks this: [1,2,3,4].

by choosing value each array, want exhaust combinations, in example, desired result be:

[1,2,3], [1,2,4], [1,3,4],[2,3,4]

order doesnt matter. i'm iterating on every possibility, , that's waaaay slow. thought first doing check make sure iterator greater 1 left of it, in case of 1,4,... fail because 3rd array doesn't have bigger 4. additionally i'd need check make sure max of each column no greater column length - (# of repeating columns - column position. example column 2 not exceed 3. think i'm going down rabbit hole.

any clever ways desired result in fewest iterations possible? modifying arrays fair game, too.


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