N = int(input())
S = input()
i = 0
a =["wa","wo","n","w?","?a","?o","?"]
while i < N:
	if S[i:i+2]=="wa" or S[i:i+2]=="wo" or S[i:i+2]=="w?" or S[i:i+2]=="?a" or S[i:i+2]=="?o" :
		i = i +2
	elif S[i:i+1]=="n" or S[i:i+1]=="?":
		i =i +1
	else:
		print("No")
		break
if i == N:
	print("Yes")