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

public class Main {
  static int m;

  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer(br.readLine());
    int n = Integer.parseInt(st.nextToken());
    m = Integer.parseInt(st.nextToken());

    int totalMasks = 1 << m;

    int[][] maskPatterns = new int[totalMasks][];
    int[] maskSize = new int[totalMasks];
    int[] maskCount = new int[totalMasks];

    char[][] patterns = new char[n][m];
    int[] masks = new int[n];

    for (int i = 0; i < n; i++) {
      String line = br.readLine().trim();
      int mask = 0;
      for (int j = 0; j < m; j++) {
        patterns[i][j] = line.charAt(j);
        if (patterns[i][j] != '?')
          mask |= (1 << j);
      }
      masks[i] = mask;
      maskCount[mask]++;
    }

    for (int mask = 0; mask < totalMasks; mask++) {
      maskPatterns[mask] = new int[maskCount[mask]];
    }

    for (int i = 0; i < n; i++) {
      int mask = masks[i];
      int code = encode(patterns[i], mask);
      maskPatterns[mask][maskSize[mask]++] = code;
    }

    long answer = 0;

    int[] projA = new int[n];
    int[] projB = new int[n];

    for (int a = 0; a < totalMasks; a++) {
      if (maskPatterns[a].length == 0)
        continue;
      for (int b = a; b < totalMasks; b++) {
        if (maskPatterns[b].length == 0)
          continue;

        int conflict = a & b;

        if (a == b) {
          int sz = maskPatterns[a].length;
          for (int i = 0; i < sz; i++) {
            projA[i] = reproject(maskPatterns[a][i], a, conflict);
          }
          Arrays.sort(projA, 0, sz);
          int i = 0;
          while (i < sz) {
            int j = i + 1;
            while (j < sz && projA[j] == projA[i])
              j++;
            long cnt = j - i;
            answer += cnt * (cnt - 1) / 2;
            i = j;
          }
        } else {
          int sza = maskPatterns[a].length;
          int szb = maskPatterns[b].length;
          for (int i = 0; i < sza; i++)
            projA[i] = reproject(maskPatterns[a][i], a, conflict);
          for (int i = 0; i < szb; i++)
            projB[i] = reproject(maskPatterns[b][i], b, conflict);
          Arrays.sort(projA, 0, sza);
          Arrays.sort(projB, 0, szb);
          int i = 0, j = 0;
          while (i < sza && j < szb) {
            if (projA[i] == projB[j]) {
              int cntA = 1, cntB = 1;
              while (i + cntA < sza && projA[i + cntA] == projA[i])
                cntA++;
              while (j + cntB < szb && projB[j + cntB] == projB[j])
                cntB++;
              answer += (long) cntA * cntB;
              i += cntA;
              j += cntB;
            } else if (projA[i] < projB[j])
              i++;
            else
              j++;
          }
        }
      }
    }

    System.out.println(answer);
  }

  static int encode(char[] pattern, int mask) {
    int code = 0;
    for (int i = 0; i < m; i++) {
      if ((mask & (1 << i)) != 0) {
        code = code * 27 + (pattern[i] - 'a' + 1);
      }
    }
    return code;
  }

  static int reproject(int code, int srcMask, int targetMask) {
    int[] vals = new int[6];
    int idx = 0;
    for (int i = 0; i < 6; i++) {
      if ((srcMask & (1 << i)) != 0) {
        vals[idx++] = code % 27;
        code /= 27;
      }
    }
    int result = 0, mul = 1;
    int[] srcBits = new int[6];
    int srcCount = 0;
    for (int i = 0; i < 6; i++) {
      if ((srcMask & (1 << i)) != 0)
        srcBits[srcCount++] = i;
    }
    for (int k = 0; k < srcCount; k++) {
      if ((targetMask & (1 << srcBits[k])) != 0) {
        result += vals[srcCount - 1 - k] * mul;
        mul *= 27;
      }
    }
    return result;
  }
}