def parse(s):
	s = s + '|'
	d = dict()
	mol, cnt = None, 0
	for c in s:
		if ord('A') <= ord(c) <= ord('Z') or c == '|':
			if mol:
				if mol not in d:
					d[mol] = 0
				d[mol] += max(1, cnt)
			mol, cnt = c, 0
		else:
			cnt = 10 * cnt + (ord(c) - ord('0'))
	return d

line1 = input().split(' ')
line2 = input()

m1, k, m2 = parse(line1[0]), int(line1[1]), parse(line2)

ans = 10**9
for m in m2:
	if m not in m1:
		ans = 0
	else:
		ans = min(ans, (m1[m] * k) // m2[m])

print(ans)