n = int(input())
S = input()

l = ["wa","wo","n"]

dp = set()
if S[0] == "w":
    dp.add(S[0])
elif S[0] == "n":
    dp.add(S[0])

elif S[0] == "?":
    dp.add("w")
    dp.add("n")


for s in S[1:]:

    ndp = set()

    for x in dp:
        if x == "n" or x == "a" or x == "o":
            if s == "n" or s == "w":
                ndp.add(s)
            elif s == "?":
                ndp.add("n")
                ndp.add("w")
        elif x == "w":
            if s == "a" or s == "o":
                ndp.add(s)
            elif s == "?":
                ndp.add("a")
                ndp.add("o")

    dp = ndp

print("Yes" if dp else "No")