legalstr = set(str(i) for i in range(1, 27)) self.ans = 0 dp = [0] * len(s) def dfs(s, i): a, b = 0, 0 if len(s) == 0: self.ans = 1 return self.ans if (dp[i] != 0): return dp[i] if s[0] in legalstr: a = dfs(s[1:], i + 1) if len(s) > 1 and s[:2] in legalstr: b = dfs(s[2:], i + 2) dp[i] = a + b return dp[i] return dfs(s, 0) 更具上述代码生成流程图（偏学术极简）