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Comment by abetusk | Hacker News Reader

The constraints stated:

  * You can never make an integer greater than the largest integer in the original list.
  * You can never make a move that results in the same integer appearing in the list more than once.

You can make a negative number and you can go lower than the smallest but not greater than the largest, so you're wrong on both counts.

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However, as a result of #1, you in fact cannot make negative integers. It’s not possible to split a nonnegative integer into two lesser-or-equal integers such that either of them is negative.

> largest integer in the original list

So if the original list was [10, 1] and negative numbers were allowed, then [10, 2, -1] would be allowed.

Oops, indeed!

I believe Sharlin is correct here. Rule #1 states `Split an integer into two smaller integers.` 1 -> [2, -1] breaks this rule due to 2 not being smaller than 1.

It does feel implied albeit forgotten given the constrained nature of the task. Opening up the door to negative numbers feels like cheating.

the only moves available are:

1. Split an integer into two smaller integers.

2. Combine (add) two integers into a larger one.

Both suggest that negative numbers are not possible.

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