There's only 1 possibility...

the 2 integers are { 0, 1 }

Everything else doesn't work. If you start {-2, -1, 0, 1, 2}

you need the positive versions of the negative numbers just to get the sum equal to zero. Then the moment you add the next number in the sequence {3}, the sum goes from 0 to 3 and it skips "1" entire.y.

{-1, 0, 1} gets you to 0

{-1, 0, 1, 2} gets you to 2

The only way to get to 1 is {0, 1} and that is an even # of integers.

{1} itself doesn't work because n>1

So average of 0 and 1 is 0.5 (so III is out).

n=2 so n is an even number. There is no case where n works and is an odd number.

I only says that n is an even number and that's the only possibility.

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