n = int(input()) S = input() dp = [0]*(n+1) dp[0] = 1 l = ["wa","wo","n"] for i in range(n): if dp[i] == 0: continue for x in l: if len(x) + i > n: continue ok = 1 for j in range(len(x)): if x[j] == S[i+j] or S[i+j] == "?": ok = 1 else: ok = 0 break if ok: # print(i,x,i+len(x)) dp[i+len(x)] = 1 # print(dp) print("Yes" if dp[-1] else "No")