[OJFord]

That's just the right solution if you know x and y (or even just x?) ahead of time isn't it?

And don't you mean "27" into register 27-x, do. 18 etc.?

[albertsondev]

Or even neither!

Much faster to find upper and lower bounds and essentially construct a hash table than to manually sort a whole list of non-trivial length.

[cjohansson]

Is it really? Building the hash can be made in linear time but iterating the values in order, especially when there might be gaps in the interval? Could be messy

[daniel-cussen]

The overhead of hashing in a hash table makes it worse than sorting algorithms without hashing.