# stackかと思ったが、スタックのlast参照するのとは違う

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

bad = 'bcdefghijklmpqrstuvxyz'
used = [0]*N
ans = 'Yes'
for i in range(N):
    if S[i] in bad:
        ans = 'No'
    if i < N-1:
        if S[i] == 'w':
            if S[i+1] == 'w' or S[i+1] == 'n':
                ans = 'No'
            if S[i+1] == '?':
                S[i+1] = 'a'
        
for i in range(N-1, -1, -1):
    if i > 0:
        if S[i] == 'a':
            if S[i-1] == 'a' or S[i-1] == 'o':
                ans = 'No'
            if S[i-1] != '?':
                S[i-1] = 'w'
        if S[i] == 'o':
            if S[i-1] == 'a' or S[i-1] == 'o':
                ans = 'No'
            if S[i-1] != '?':
                S[i-1] = 'w'

print(ans)