Calculate the sum of largest 2 element of an array.

max_2_sum

#Calculate the sum of largest 2 elements of an array.

def max_2_sum(arr)
  arr.inject([0, 0]) do |largest, el|
    if largest[0] < el
      largest[1] = largest[0]
      largest[0]  = el
    elsif largest[1] < el
      largest[1] = el
    end
    largest
  end.inject(:+)
end

#or use shortcut

def max_2_sum(arr)
  sorted = arr.sort
  sorted[-1] + sorted[-2]
end

p max_2_sum([3, 4, 5, -2, -3, 5, 9])