n = int(input()); s = input()
i = 0; ans = "Yes"
while i<n:
    if i==n-1 and s[i]=="?": i += 1
    elif s[i]=="n" or s[i:i+2] in {"??","?n"}: i += 1
    elif s[i:i+2] in {"wa","wo","w?","?a","?o"}: i += 2
    else: ans = "No"; i += 1
print(ans)