You are given a map of a building, and your task is to count the number of its rooms. The size of the map is n×m squares, and each square is either floor or wall. You can walk left, right, up, and down through the floor squares.
A room is completely surrounded by walls on all sides and can have walls in between.

Input

The first input line has two integers n and m: the height and width of the map.

Then there are n lines of m characters describing the map. Each character is either . (floor) or # (wall).

Output

Print one integer: the number of rooms.

Constraints

1≤n,m≤1000