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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;

namespace test
{
    class Program
    {
        static void Main(string[] args)
        {
            var input = ReadArrayInt();
            var H = input[0];
            var W = input[1];
            var grid = new char[H, W];
            for (int i = 0; i < H; i++)
            {
                var line = Read();
                for (int j = 0; j < W; j++)
                {
                    grid[i, j] = line[j];
                }
            }
            var ans = 0L;
            for (int i = 0; i < H; i++)
            {
                for (int j = 0; j < W; j++)
                {
                    var b = 0;
                    var w = 0;
                    var que = new Queue<int[]>();
                    if (grid[i, j] == '#')
                    {
                        b++;
                        grid[i, j] = '*';
                        if (j > 0) que.Enqueue(new int[] { i, j - 1, 2 });
                        if (j < W - 1) que.Enqueue(new int[] { i, j + 1, 2 });
                        if (i > 0) que.Enqueue(new int[] { i - 1, j, 2 });
                        if (i < H - 1) que.Enqueue(new int[] { i + 1, j, 2 });
                    }
                    while (que.Count() > 0)
                    {
                        var now = que.Dequeue();
                        var height = now[0];
                        var width = now[1];
                        var bw = now[2];
                        if (grid[height, width] == '*') continue;
                        if (grid[height, width] == '#')
                        {
                            if (bw == 2) continue;
                            else b++;
                        }
                        if (grid[height, width] == '.')
                        {
                            if (bw == 1) continue;
                            else w++;
                        }
                        grid[height, width] = '*';
                        if (bw == 1)
                        {
                            if (width > 0) que.Enqueue(new int[] { height, width - 1, 2 });
                            if (width < W - 1) que.Enqueue(new int[] { height, width + 1, 2 });
                            if (height > 0) que.Enqueue(new int[] { height - 1, width, 2 });
                            if (height < H - 1) que.Enqueue(new int[] { height + 1, width, 2 });
                        }
                        else if (bw == 2)
                        {
                            if (width > 0) que.Enqueue(new int[] { height, width - 1, 1 });
                            if (width < W - 1) que.Enqueue(new int[] { height, width + 1, 1 });
                            if (height > 0) que.Enqueue(new int[] { height - 1, width, 1 });
                            if (height < H - 1) que.Enqueue(new int[] { height + 1, width, 1 });
                        }
                    }
                    ans += b * w;
                }
            }

            Console.WriteLine(ans);
            Console.ReadLine();
        }

        static string Read() { return Console.ReadLine(); }
        static int ReadInt() { return int.Parse(Read()); }
        static long ReadLong() { return long.Parse(Read()); }
        static int[] ReadArrayInt() { return Read().Split(' ').Select(s => int.Parse(s)).ToArray(); }
        static long[] ReadArrayLong() { return Read().Split(' ').Select(s => long.Parse(s)).ToArray(); }
    }
}