Cody's Jams: https://www.acmicpc.net/problem/12034

codys_jams.py

prices = [9, 9, 12, 12, 12, 15, 16, 20]
new_prices = []

# The lowest price has to be a reduces price
# Then calculate the original price from that
# remove both from the prices list and do it again

def solve (prices, new_prices):
	if len(prices) == 0:
		return new_prices

	lower = prices.pop(0)
	higher = lower * (4/3)
	index = prices.index(higher)
	prices.pop(index)

	new_prices.append(lower)
	
	return solve(prices, new_prices)

print(solve(prices, new_prices))