#include <bits/stdc++.h>
using namespace std;
const long long N = 1e3 + 10;
long long n, m, ans, h[N][N];
char ar[N][N];
bool get(long long i, long long j) {
  long long x = h[i][j];
  i -= x;
  if (i < 0) return 0;
  if (h[i][j] != x) return 0;
  i -= x;
  if (i < 0) return 0;
  return h[i][j] >= x;
}
bool ok(long long row, long long l, long long r) {
  long long x = h[row][l];
  if (ar[row][l] != ar[row][r]) return 0;
  row -= x;
  if (ar[row][l] != ar[row][r]) return 0;
  row -= x;
  return ar[row][l] == ar[row][r];
}
long long choose2(long long x) { return (x * (x - 1)) / 2; }
long long solve(vector<bool> &vec, long long row) {
  assert(vec.size() == m);
  long long res = 0;
  for (long long i = 0; i < vec.size(); i++) {
    if (!vec[i]) continue;
    long long r = i + 1;
    while (r < vec.size() && vec[r] && h[row][i] == h[row][r] && ok(row, i, r))
      r++;
    res += choose2(r - i + 1);
    i = r - 1;
  }
  return res;
}
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> m;
  for (long long i = 0; i < n; i++)
    for (long long j = 0; j < m; j++) cin >> ar[i][j];
  for (long long j = 0; j < m; j++) h[0][j] = 1;
  for (long long i = 1; i < n; i++)
    for (long long j = 0; j < m; j++) {
      if (ar[i][j] == ar[i - 1][j])
        h[i][j] = h[i - 1][j] + 1;
      else
        h[i][j] = 1;
    }
  for (long long i = 0; i < n; i++) {
    vector<bool> vec;
    for (long long j = 0; j < m; j++) vec.push_back(get(i, j));
    ans += solve(vec, i);
  }
  cout << ans << endl;
}
