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

dp = [[False] * 26 for _ in range(N)]
if S[0] == '?':
    for j in range(26):
        dp[0][j] = True  # S == "?..."
if S[0] == 'n':
    dp[0][ord('n') - ord('a')] = True  # S == "n..."
if S[0] == 'w':
    dp[0][ord('w') - ord('a')] = True  # S == "w..."
if S[0] == 'a':  # S == "a..."
    print("No")
    exit(0)
if S[0] == 'o':  # S == "o..."
    print("No")
    exit(0)

for i in range(1, N):
    for j in range(26):
        if dp[i - 1][j]:
            if j == ord('w') - ord('a'):
                if S[i] == 'a':
                    dp[i][ord('a') - ord('a')] = True  # w -> a
                if S[i] == 'o':
                    dp[i][ord('o') - ord('a')] = True  # w -> o
                if S[i] == '?':
                    dp[i][ord('a') - ord('a')] = True  # w -> a
                    dp[i][ord('o') - ord('a')] = True  # w -> o
            else:
                if S[i] == 'w':
                    dp[i][ord('w') - ord('a')] = True  # a -> w, o -> w, n -> w
                if S[i] == 'n':
                    dp[i][ord('n') - ord('a')] = True  # a -> n, o -> n, n -> n
                if S[i] == '?':
                    dp[i][ord('w') - ord('a')] = True  # a -> w, o -> w, n -> w
                    dp[i][ord('n') - ord('a')] = True  # a -> n, o -> n, n -> n

ans = False
if dp[N - 1][ord('a') - ord('a')]:
    ans = True  # S == "...a"
if dp[N - 1][ord('o') - ord('a')]:
    ans = True  # S == "...o"
if dp[N - 1][ord('n') - ord('a')]:
    ans = True  # S == "...n"

if ans:
    print("Yes")
else:
    print("No")