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

for s in S:
    if s not in ["w", "a", "o", "n", "?"]:
        exit(print("No"))

idx = 0
while idx < len(S):
    if S[idx] == "n":
        idx += 1
    elif S[idx] == "w":
        if idx+1 == len(S):
            print("No")
            break
        elif S[idx+1] in ["a", "o", "?"]:
            idx += 2
        else:
            print("No")
            break
    elif S[idx] == "?":
        if idx+1 == len(S):
            idx += 1
        elif S[idx+1] in ["w", "n"]:
            idx += 1
        elif S[idx+1] in ["a", "o"]:
            idx += 2
        else:
            idx += 1
    else:
        print("No")
        break
else:
    print("Yes")