n = int(input())
s = input()
dp0 = [0]*(n+1)
dp1 = [0]*(n+1)
dp0[0] = 1
for i in range(n):
	if s[i] == "w":
		if dp0[i]: dp1[i+1] = 1
	elif s[i] == "a" or s[i] == "o":
		if dp1[i]: dp0[i+1] = 1
	elif s[i] == "n":
		if dp0[i]: dp0[i+1] = 1
	elif s[i] == "?":
		if dp0[i]:
			dp1[i+1] = 1
			dp0[i+1] = 1
		if dp1[i]: dp0[i+1] = 1

if dp0[n]: print("Yes")
else: print("No")