def numDecodings(s): if not s: return 0 dp = [0]*(len(s)+1) dp[0] = 1 for i in range(1,len(dp)): if s[i-1] != "0": dp[i] = dp[i-1] if i != 1 and "09"<s[i-2:i]<"27": dp[i]+=dp[i-2] return dp[-1] if __name__ == '__main__': s = input() res = numDecodings(s) print(res)