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 Python (3.4.3) (judge verdict: Accepted)

from collections import deque

H,W=map(int,input().split())
S=[input() for i in range(H)]

CHECK=[[0]*W for i in range(H)]
ANSLIST=[]

for i in range(H):
    for j in range(W):
        if CHECK[i][j]==1:
            continue
        QUE = deque()
        QUE.append((i,j))
        BC=0
        WC=0

        while QUE:
            x,y=QUE.pop()
            if CHECK[x][y]==1:
                continue

            
            CHECK[x][y]=1
            #print(x,y,QUE,CHECK)

            if S[x][y]=="#":
                BC+=1
            else:
                WC+=1


            for k,l in [(x+1,y),(x-1,y),(x,y+1),(x,y-1)]:
                #print("!",k,l,x,y)
                if k<0 or l<0 or k>=H or l>=W:
                    #print("?",k,l)
                    continue
                if CHECK[k][l]==1:
                    continue

                if S[k][l]!=S[x][y]:
                    QUE.appendleft((k,l))
                    #print(x,y)

        ANSLIST.append((BC,WC))
        #print(i,j,ANSLIST,CHECK)

ANS=0
for a,b in ANSLIST:
    ANS+=a*b

print(ANS)