How to return an array which size isn't constant

Question

https://code.sololearn.com/cN5j7Ok4P1yU/?ref=app

Answer 1

you have an Variable Length Array(VLA) with static storage specification and this is not allowed by the C99 standard.

C99 Standard: 6.7.5.2/10:
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Array objects declared with the static or extern storage class specifier cannot have a variable length array (VLA) type.
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