apple_stock.rb

# Convert to unit test
require "minitest/autorun"

class StockTest < Minitest::Test
  def test_picking_best_time_to_buy
    stock = [1,8,3,0,1,54,29,1,3,10,49,10,39,28,41,1,3]

    prices = Array.new
    stock.each_with_index  do |buy_price, buy_index|
      stock.each_with_index do |sell_price, sell_index|
        if buy_index < sell_index
          value = sell_price - buy_price
          hr = {sell_index: sell_index, buy_index: buy_index, value: value}
          prices << hr
       end
      end
    end  
    max = prices.max_by{|k,v| k[:value] }
        
    assert_equal 3, max[:buy_index]
    assert_equal 5, max[:sell_index]
    assert_equal 54, max[:value]
  end
end