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using System;
using System.Collections.Generic;

namespace Hef.TopCoder.Srm145.Div2
{
  public class ImageDithering
  {
    public int count(string dithered, string[] screen)
    {
      // setup
      List<char> diths = new List<char>(dithered.ToCharArray());
      char[][] grid = new char[screen.Length][];
      for (int i = 0; i < screen.Length; i += 1)
        grid[i] = screen[i].ToCharArray();

      // find dithering colors next to each other
      int result = 0;
      for (int i = 0; i < grid.Length; i += 1)
      {
        for (int j = 0; j < grid[i].Length; j += 1)
        {
          if (diths.Contains(grid[i][j]) && (
               (i > 0 && diths.Contains(grid[i - 1][j])) // above
            || (i < grid.Length - 1 && diths.Contains(grid[i + 1][j])) // below
            || (j > 0 && diths.Contains(grid[i][j - 1])) // left
            || (j < grid[i].Length - 1 && diths.Contains(grid[i][j + 1])) // right
            ))
          {
            result += 1;
          }
        }
      }

      return result;
    }
  }
}