The smallest difference

Problem

Write a function that takes a list of numbers and returns the smallest difference there is between two of them.

With 1, 5, 3, 19, 18 and 25 the answer is 1, because 18 and 19 are the two that sit closest together.

The rules: the difference is never negative, so measure the distance between the two, not which one comes first. If a number is repeated, the difference is 0. With fewer than two numbers there is no pair to compare: in that case you return 0.

You can compare all of them against all the others, but there is a shorter road: sort the list and compare only neighbors, because the two closest numbers always end up side by side.

Examples

• Two that sit close

  [1, 5, 3, 19, 18, 25] → 1

• In a row

  [4, 3, 2, 6] → 1

• Far apart

  [30, 5, 20, 9] → 4

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

You start with this

def min_difference(numbers):
    pass

function minDifference(numbers) {
}