n=2+int(input())
s="nn"+input()
q=[0]*n
q[0]=1
q[1]=1
for i in range(2,n):
	if s[i] in ["n","?"]:
		q[i]|=q[i-1]
	if s[i-1]+s[i] in ["wa","wo","?a","?o","w?","??"]:
		q[i]|=q[i-2]
print(["No","Yes"][q[n-1]])