using System;
using System.Linq;

namespace P02SquaresInMatrix
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] arr = Console.ReadLine().Split(" ").Select(int.Parse).ToArray();

            int rows = arr[0];
            int cols = arr[1];
            int count = 0;

            var matrix = new char[rows, cols];

            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                char[] letters = Console.ReadLine()
                    .Split(" ", StringSplitOptions.RemoveEmptyEntries)
                    .Select(char.Parse)
                    .ToArray();

                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    matrix[row, col] = letters[col];


                }
            }

            for (int i = 0; i < matrix.GetLength(0)-1; i++)
            {

                for (int j = 0; j < matrix.GetLength(1)-1; j++)
                {

                    if(matrix[i, j] == matrix[i, j+1]
                        && matrix[i,j+1] == matrix [i+1,j]
                        && matrix[i+1,j] == matrix[i + 1, j + 1])
                    {
                        count++;
                    }


                }
            }

            Console.WriteLine(count);

        }
    }
}