How many strings can be obtained by applying the following operation on a string S exactly K times: "choose one lowercase English letter and insert it somewhere"?
The answer can be enormous, so print it modulo (10^9+7).

-----Constraints-----
- K is an integer between 1 and 10^6 (inclusive).
- S is a string of length between 1 and 10^6 (inclusive) consisting of lowercase English letters.

-----Input-----
Input is given from Standard Input in the following format:
K
S

-----Output-----
Print the number of strings satisfying the condition, modulo (10^9+7).

-----Sample Input-----
5
oof

-----Sample Output-----
575111451

For example, we can obtain proofend, moonwolf, and onionpuf, while we cannot obtain oofsix, oofelevennn, voxafolt, or fooooooo.

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