#abc307h. [abc307_h]Marquee
[abc307_h]Marquee
Problem Statement
There is a length string consisting of uppercase and lowercase English letters displayed on an electronic bulletin board with a width of . The string scrolls from right to left by a width of one character at a time.
The display repeats a cycle of states, with the first character of appearing from the right edge when the last character of disappears from the left edge.
For example, when and ABC
, the board displays the following seven states in a loop:
ABC..
BC...
C....
....A
...AB
..ABC
.ABC.
(.
represents a position where no character is displayed.)
More precisely, there are distinct states for in which the display is as follows.
- Let be the remainder when is divided by . The -th position from the left of the board displays the -th character of when , and nothing otherwise.
You are given a length string consisting of uppercase English letters, lowercase English letters, .
, and _
.
Find the number of states among the states of the board that coincide except for the positions with _
.
More precisely, find the number of states that satisfy the following condition.
- For every , one of the following holds.
- The -th character of is
_
. - The character displayed at the -th position from the left of the board is equal to the -th character of .
- Nothing is displayed at the -th position from the left of the board, and the -th character of is
.
.
- The -th character of is
Constraints
- and are integers.
- is a string of length consisting of uppercase and lowercase English letters.
- is a string of length consisting of uppercase and lowercase English letters,
.
, and_
.
Input
The input is given from Standard Input in the following format:
Output
Print the answer.
Sample Input 1
3 5
ABC
..___
Sample Output 1
3
There are three desired states, where the board displays ....A
, ...AB
, ..ABC
.
Sample Input 2
11 15
abracadabra
__.._________ab
Sample Output 2
2
Sample Input 3
20 30
abaababbbabaabababba
__a____b_____a________________
Sample Output 3
2
Sample Input 4
1 1
a
_
Sample Output 4
1