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

WAON={"w","a","o","n","?"}

for s in S:
    if s in WAON:
        pass
    else:
        print("No")
        exit()

if S[-1]=="w":
    print("No")
    exit()

if S[0]=="a" or S[0]=="o":
    print("No")
    exit()

for i in range(N):
    if S[i]=="w":
        if S[i+1]=="w" or S[i+1]=="n":
            print("No")
            exit()

        if S[i+1]=="?":
            S[i+1]="a"
    if S[i]=="a" or S[i]=="o":
        if S[i-1]=="w" or S[i-1]=="?":
            pass
        else:
            print("No")
            exit()

print("Yes")