n, m = map(int,input().split())
s = input()
assert 1 <= n <= 10 ** 5
assert 1 <= m <= 10 ** 5

w = s.count("W")
a = s.count("A")
c = s.count("C")
assert w == n
assert a == n + m
assert c == m
assert len(s) == 2*(n+m)

pivot = 0
for i in range(2*(n+m)):
	if s[i] == "C":
		mode = 0
		while pivot < i and mode == 0:
			if s[pivot] == "A":
				mode = 1
			pivot += 1
		if mode == 0:
			print("No")
			exit()

for i in range(2*(n+m)):
	if s[i] == "W":
		mode = 0
		while pivot < 2*(n+m) and mode == 0:
			if s[pivot] == "A":
				mode = 1
			pivot += 1
		if mode == 0:
			print("No")
			exit()

print("Yes")