题目描述
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).
Examples
Input
5
oof
Output
575111451
Input
37564
whydidyoudesertme
Output
318008117
输入格式
见题面
输出格式
见题面
样例输入
5
oof
样例输出
575111451