from collections import deque

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

que = deque()
for s in S:
    que.append(s)

while que:
    el = que.popleft()
    if el == 'n':
        continue
    if el == 'w':
        if que and que[0] in ('?', 'a', 'o'):
            que.popleft()
            continue
        else:
            print("No")
            exit()
    if el == '?':
        if que and que[0] in ('a', 'o'):
            que.popleft()
        continue
    print("No")
    exit()
print("Yes")