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

dp = []

for i in range(N+1):
    dp.append([False]*2)

dp[0][0] = True

#0 = a,o,n
#1 = w

for i,v in enumerate(S):
    if v == "w":
        if dp[i][0] == True:
            dp[i+1][1] = True
        else:
            print("No")
            exit()
    elif v == "a" or v == "o":
        if dp[i][1] == True:
            dp[i+1][0] = True
        else:
            print("No")
            exit()
    elif v == "n":
        if dp[i][0] == True:
            dp[i+1][0] = True
        else:
            print("No")
            exit()
    elif v == "?":
        if dp[i][0] == True:
            dp[i+1][0] = True
            dp[i+1][1] = True
        else:
            dp[i+1][0] = True
    else:
        print("No")
        exit()

if dp[-1][0]:
    print("Yes")
else:
    print("No")

#print(*dp, sep = "\n")