import java.io.*;
import java.util.*;

public class Matrice {
    static int[] dX = new int[]{1,1,-1,-1};
    static int[] dY = new int[]{1,-1,-1,1};

    public static boolean inside(int X, int Y, char c, char[][] map) {
    	if (X < 0) return false;
    	if (Y < 0) return false;
    	if (map.length <= Y) return false;
    	if (map[0].length <= X) return false;

	return map[Y][X] == c;
    }

    public static void main(String[] args) throws IOException {
	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

	String s = br.readLine();
	String[] parts = s.split(" ");
	int H = Integer.parseInt(parts[0]);
	int W = Integer.parseInt(parts[1]);

	char[][] map = new char[H][];

	for (int i = 0; i < H; i++) {
	   map[i] = br.readLine().toCharArray();
	}

	int maxSize = 1000;
	int count = 0;
	int sizecount = 0;
	for (int size = 2; size <= maxSize; size++) {
	    sizecount = 0;
	    for (int Y = 0; Y < H; Y++) {
		for (int X = 0; X < W; X++) {
		    char origin = map[Y][X];
		    for (int i = 0; i < 4; i++) {
		    	int dx = dX[i];
		    	int dy = dY[i];
			boolean ok = true;

			for (int yy = 0; yy < size; yy++) {
		  	    if (!ok) break;
			    for (int xx = 0; xx < size-yy; xx++) {
			    	int x = X + xx*dx;
			    	int y = Y + yy*dy;
				//System.out.printf("[%d, %d] [%d, %d]\n", X, Y, x, y);
				if (!inside(x,y,origin, map)) {
				    ok = false;
				    break;
				}
			    }
			}

			if (ok) {
			    sizecount++;
			}
		    }
		}
	    }
	    count += sizecount;
	    if (sizecount == 0) break;
	}

	System.out.println(count);



    }
}