using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        List<string> pics = new List<string>();

        //pics.Add("aaaba"); pics.Add("ababa") ; pics.Add("aaaca");

        pics.Add("bbba"); pics.Add("abba") ; pics.Add("acaa"); pics.Add("aaac");

        Console.WriteLine("count: " + Solve(pics) );

    }

    private static void dfs(List<string> pics, int i, int j, Boolean[,] vis){

        int h = pics.Count;

        int w = pics[0].Length;

        if(vis[i,j] == true) return;

        vis[i,j] = true;

        if( i < h-1 && pics[i+1][j] == pics[i][j]){

            dfs(pics, i+1, j, vis);

        }

        if( j < w -1 && pics[i][j+1] == pics[i][j]){

            dfs(pics, i, j+1, vis);

        }

        if( i > 0 && pics[i-1][j] == pics[i][j]){

            dfs(pics, i-1, j, vis);

        }

        if(j > 0 && pics[i][j-1] == pics[i][j]){

            dfs(pics, i, j-1, vis);

        }       

    }

    public static int Solve(List<string> pics){

        int h = pics.Count;

        int w = pics[0].Length;

        Boolean[,] vis= new Boolean[h, w];

        int count = 0;

        char currChar = pics[0][0];

        for(int i=0;i<h; i++){

            for(int j=0;j<w; j++){

                if( !vis[i, j]){

                    dfs(pics, i, j, vis);

                    count++;

                }

            }

        }

        return count;

    }

}