Problem:
Score : 300 points

Problem Statement

There is a grid with H rows and W columns, where each square is painted black or white.

You are given H strings S_1, S_2, ..., S_H, each of length W.
If the square at the i-th row from the top and the j-th column from the left is painted black, the j-th character in the string S_i is #; if that square is painted white, the j-th character in the string S_i is ..

Find the number of pairs of a black square c_1 and a white square c_2 that satisfy the following condition:

There is a path from the square c_1 to the square c_2 where we repeatedly move to a vertically or horizontally adjacent square through an alternating sequence of black and white squares: black, white, black, white...

Constraints

1 \leq H, W \leq 400

|S_i| = W (1 \leq i \leq H)

For each i (1 \leq i \leq H), the string S_i consists of characters # and ..

Input

Input is given from Standard Input in the following format:

H W
S_1
S_2
:
S_H

Output

Print the answer.

Sample Input 1

3 3
.#.
..#
#..

Sample Output 1

10

Some of the pairs satisfying the condition are ((1, 2), (3, 3)) and ((3, 1), (3, 2)), where (i, j) denotes the square at the i-th row from the top and the j-th column from the left.

Sample Input 2

2 4
....
....

Sample Output 2

0

Sample Input 3

4 3
###
###
...
###

Sample Output 3

6

Solution in Julia (0.5.0) (judge verdict: Accepted)

parseInt(x) = parse(Int, x)
parseMap(x::Array{SubString{String},1}) = map(parseInt, x)
function root(uf::Array{Int,1},x);s=x;while uf[s]>0;s=uf[s];end;s;end
same(uf::Array{Int,1},x,y)=root(uf,x)==root(uf,y)?true:false;
function unite(uf::Array{Int,1},x,y);l=root(uf,x);r=root(uf,y);if l!=r;if uf[l]<uf[r];uf[l]+=uf[r];uf[r]=l;else;uf[r]+=uf[l];uf[l]=r;end;end;end

function main()
	h,w = readline() |> split |> parseMap
	g = String["" for i in 1:h]
	c = zeros(Int,h*w)
	uf = -ones(Int,h*w)
	for i in 1:h
		g[i] = readline() |> chomp
	end
	for i in 1:h
		for j in 1:w
			x = (i-1)*w+j
			if g[i][j]=='#'
				c[x] = 1
			end
			if i>1
				if c[(i-2)*w+j]!=c[x]
					unite(uf,(i-2)*w+j,x)
				end
			end
			if j>1
				if c[(i-1)*w+j-1]!=c[x]
					unite(uf,(i-1)*w+j-1,x)
				end
			end
		end
	end
	bd = Dict{Int,Int}()
	wd = Dict{Int,Int}()
	for i in 1:h*w
		r = root(uf,i)
		if c[i]==0
			if haskey(wd,r)
				wd[r] += 1
			else
				wd[r] = 1
			end
		else
			if haskey(bd,r)
				bd[r] += 1
			else
				bd[r] = 1
			end
		end
	end
	ans = 0
	for i in keys(bd)
		if haskey(wd,i)
			ans += bd[i]*wd[i]
		end
	end
	println(ans)
end

main()