Find the minimum and maximum integers in an array, without using builtins
Jelly, 3 bytes

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Sort the array, and then takes the 0.5-th element.

Jelly uses 1-indexing, and floating points indexing means take its floor and its ceil.

So the 0.5-th element would give you the 0th element and the 1st element.

The 0th element is the last element.