N = int(input())
S = input()


S = list(S)
n = len(S)
i = 0
# ?は任意の文字を表す
while i < n:
    if i == n - 1:
        if S[i] != "?" and S[i] != "n":
            print("No")
            exit()
        else:
            break
    if (
        S[i] == "w"
        and S[i + 1] == "o"
        or S[i] == "?"
        and S[i + 1] == "o"
        or S[i] == "w"
        and S[i + 1] == "?"
        or S[i] == "?"
        and S[i + 1] == "a"
    ):
        i += 2
    elif S[i] == "w" and S[i + 1] == "a":
        i += 2
    elif S[i] == "n" or S[i] == "?":
        i += 1
    else:
        print("No")
        exit()
print("Yes")