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

def is_wawon_string(S):
    i = 0
    while i < len(S):
        if S[i] == "w":
            if i + 1 < len(S) and S[i + 1] in ["a", "o"]:
                i += 2
            else:
                return False
        elif S[i] == "n":
            i += 1
        else:
            return False
    return True

if "?" not in S:
    if is_wawon_string(S):
        print("Yes")
    else:
        print("No")
else:
    for c in ["a", "n", "o", "w"]:
        new_S = S.replace("?", c)
        if is_wawon_string(new_S):
            print("Yes")
            break
    else:
        print("No")