rules = {}
polymer = []
with open("sample.txt") as f:
	template, instructions = f.read().split('\n\n')
	for element in template:
		polymer.append(element)
	for rule in instructions.split('\n'):
		a, b = rule.split(' -> ')
		rules[a] = b

def step(polymer):
	polymer2 = []
	for i, element in enumerate(polymer):
		polymer2.append(element)
		if i < len(polymer) - 1:
			
			pair = element + polymer[i+1]
			if pair in rules:
				insertion = rules[pair]
				polymer2.append(insertion)
	return polymer2


part1 = polymer.copy()
for i in range(10):
	part1 = step(part1)

from collections import Counter
c = Counter(part1)
f = c.most_common()
most = f[0][1]
least = f[-1][1]
print(most - least)

c2 = Counter()
def step2(polymer):