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]!=s
		s=uf[s]
	end
	s
end
function same(uf::Array{Int,1},x,y)
	root(uf,x)==root(uf,y)?true:false
end
function unite(uf::Array{Int,1},x,y)
	l = root(uf,x)
	r = root(uf,y)
	if l < r
		uf[r] = l
	elseif l > r
		uf[l] = r
	end
end

function main()
	h,w = readline() |> split |> parseMap
	s = String["" for i in 1:h]
	for i in 1:h
		s[i] = readline() |> chomp
	end
	uf = Int[i for i in 1:h*w]
	for i in 1:h
		for j in 1:w
			if i>1
				if s[i][j]!=s[i-1][j]
					unite(uf,w*(i-1)+j,w*(i-2)+j)
				end
			end
			if i<h
				if s[i][j]!=s[i+1][j]
					unite(uf,w*(i-1)+j,w*i+j)
				end
			end
			if j>1
				if s[i][j]!=s[i][j-1]
					unite(uf,w*(i-1)+j,w*(i-1)+j-1)
				end
			end
			if j<w
				if s[i][j]!=s[i][j+1]
					unite(uf,w*(i-1)+j,w*(i-1)+j+1)
				end
			end
		end
	end
	b = Dict{Int,Int}()
	v = Dict{Int,Int}()
	for i in 1:h
		for j in 1:w
			if s[i][j]=='#'
				r = root(uf,w*(i-1)+j)
				if haskey(b,uf[r])
					b[uf[r]]+=1
				else
					b[uf[r]] = 1
				end
			else
				r = root(uf,w*(i-1)+j)
				if haskey(v,uf[r])
					v[uf[r]]+=1
				else
					v[uf[r]] = 1
				end
			end
		end
	end
	ans = 0
	for k in keys(b)
		if haskey(v,k)
			ans += b[k]*v[k]
		end
	end
	println(ans)
end

main()