Splitting the honey

Problem

The sisters Rosa and Lidia Paredes look after the beehives their grandfather left them. At the end of the harvest they split the combs, but a comb is never cut: each one goes whole to one sister or the other. They both want to take home weights as close as possible.

Write a function that takes combs, a list of positive whole numbers with the weight of each comb (it may be empty and weights may repeat), and returns a whole number: the smallest possible difference between the weight Rosa takes and the weight Lidia takes. Every comb gets handed out, and one sister may end up with none.

With [3, 3, 2, 2, 2], Rosa takes the two 3s and Lidia the three 2s:

6 against 6, so it returns 0. With [7, 3, 2] the most even split is 7 against 5, and it returns 2. With no combs, both take 0 and the difference is 0.

Examples

• The example

  [3, 3, 2, 2, 2] → 0

• It never comes out even

  [7, 3, 2] → 2

• One comb outweighs all the others together

  [20, 3, 4, 5] → 8

• The combs that go together are not next to each other

  [2, 5, 1, 4] → 0

• No combs

  [] → 0

Besides these, the challenge has hidden tests that are revealed when you submit your solution.

You start with this

def smallest_gap(combs):
    pass

function smallestGap(combs) {
}