n = int(input())
s = input().strip()

state0 = True
state1 = False

for i in range(n):
    current_char = s[i]
    new_state0 = False
    new_state1 = False
    
    if state0:
        # Check if can take 'n' here
        if current_char == 'n' or current_char == '?':
            new_state0 = True
        # Check if can start a 'w' followed by 'a'/'o'
        if current_char == 'w' or current_char == '?':
            if i < n - 1:
                new_state1 = True
    
    if state1:
        # Check if current_char can be 'a' or 'o'
        if current_char in {'a', 'o', '?'}:
            new_state0 = True
    
    state0, state1 = new_state0, new_state1
    
    if not (state0 or state1):
        break

print("Yes" if state0 else "No")