atcoder#ABC301F. [ABC301F] Anti-DDoS

[ABC301F] Anti-DDoS

Score : 500500 points

Problem Statement

A DDoS-type string is a string of length 44 consisting of uppercase and lowercase English letters satisfying both of the following conditions.

  • The first, second, and fourth characters are uppercase English letters, and the third character is a lowercase English letter.
  • The first and second characters are equal.

For instance, DDoS and AAaA are DDoS-type strings, while neither ddos nor IPoE is.

You are given a string SS consisting of uppercase and lowercase English letters and ?. Let qq be the number of occurrences of ? in SS. There are 52q52^q strings that can be obtained by independently replacing each ? in SS with an uppercase or lowercase English letter. Among these strings, find the number of ones that do not contain a DDoS-type string as a subsequence, modulo 998244353998244353.

Notes

A subsequence of a string is a string obtained by removing zero or more characters from the string and concatenating the remaining characters without changing the order. For instance, AC is a subsequence of ABC, while RE is not a subsequence of ECR.

Constraints

  • SS consists of uppercase English letters, lowercase English letters, and ?.
  • The length of SS is between 44 and 3×1053\times 10^5, inclusive.

Input

The input is given from Standard Input in the following format:

SS

Output

Print the answer.

DD??S
676

When at least one of the ?s is replaced with a lowercase English letter, the resulting string will contain a DDoS-type string as a subsequence.

????????????????????????????????????????
858572093

Find the count modulo 998244353998244353.

?D??S
136604