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At HackerEarth we love play checkers and we play it a lot! However, we play a very specific kind of checkers. Our game is played on 32x32 board. If you are a programmer, you probably know why the board size is 32. Maybe we will describe details of the game in a future challenge, but for now, the only thing you have to know is that we represent the board as a 2 dimensional table where '_' denotes a white field while '#' denotes a black field. A valid board looks like this:

_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_
_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#
#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_

You are given a big 2 dimensional table S and your task is to find out how many occurrences of a valid board are in S.

Input format:

In the first line there are two integers N, M denoting the number of rows and the number of columns of the input table S. N lines follow. Each of them consisting of M characters. The j-th character in the i-th of these lines denotes the j-th character in the i-th row of S. All characters are either "_" or "#".

Output:

In a single line output the number of occurrences of a valid board in S.

Constraints:

1 <= N <= 2000
1 <= M <= 2000

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