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Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.

Statement

 Goal

You have just inherited of a small plot of land of width W and height H with some trees on it. You want to grow a forest, but you have only 1 seed to plant. Find the maximum number of trees after 33 years you can have by planting the seed at the best place.

Rules:
-Seeds need 10 years to grow into a tree.
-Trees produce 4 seeds around them after one year.
-Trees may already be present on your land. They will also produce seeds after one year.

Year 0 : X is your one and only seed and Y is a tree already present.

. . . . .

. X . . .

. . . . .

. . . . .

. . . . Y


Year 1 : Trees produce seeds after one year.

. . . . .

. X . . .

. . . . .

. . . . X

. . . X Y


Year 10 : Your seed is now a tree. Congratulations!

. . . . .

. Y . . .

. . . . .

. . . . X

. . . X Y


Year 11 : Your new tree starts to produce seeds after a year.

. X . . .

X Y X . .

. X . . .

. . . . Y

. . . Y Y


Year 12 : The old trees in the corner also keep spreading.

. X . . .

X Y X . .

. X . . X

. . . X Y

. . X Y Y


Year 33 : Finally you have a tiny forest of 21 trees!

Y Y Y X .

Y Y Y Y Y

Y Y Y Y Y

X Y Y Y Y

. Y Y Y Y


Maybe if you plant the seed at another place you can get a bigger forest in the end.
When you will find the best place, you will need to give the number of trees you get after 33 years.
Input
Line 1 : an integer W for the width of the parcel.
Line 2 : an integer H for the height of the parcel.
Next H lines : each line of the land, with trees (Y) or grass (.).
Output
Line 1 : an integer N for the number of trees you can have on your land after 33 years by planting your seed at the best place.
Constraints
1 <= W <= 40
1 <= H <= 40
Example
Input
5 5 ..... ..... ..... ..... .....
Output
13

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