count_of_positives_sum_of_negatives.md

Count of positives / sum of negatives

Description

Given an array of integers.

Return an array, where the first element is the count of positives numbers and the second element is sum of negative numbers. 0 is neither positive nor negative.

If the input is an empty array or is null, return an empty array.

Example

For input [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -11, -12, -13, -14, -15], you should return [10, -65].

My Solution

def count_positives_sum_negatives(lst)
  return [] if lst.empty?
  positive, negative = lst.partition(&:positive?)
  [positive.count, negative.sum]
end