#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <cassert>
#include <string>
#include <cstring>
#include <bitset>
#include <random>
#include <chrono>
#include <iomanip>
/*
#pragma GCC optimize ("Ofast")
#pragma GCC target("fma,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#pragma GCC optimize("unroll-loops")
*/
#define FOR(i, a, b) for(int i = a; i < (int) b; i++)
#define F0R(i, a) FOR (i, 0, a)
#define ROF(i, a, b) for(int i = a; i >= (int) b; i--)
#define R0F(i, a) ROF(i, a, 0)
#define GO(i, a) for (auto i : a)
#define rsz resize
#define eb emplace_back
#define pb push_back
#define sz(x) (int) x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pii> vpii;
typedef vector<vi> vvi;
typedef vector<vpii> vvpii;
typedef long long i64;
typedef vector<i64> vi64;
typedef vector<vi64> vvi64;
typedef pair<i64, i64> pi64;
typedef vector<pi64> vpi64;
const int dr[] = {+1, -1, +0, +0, +1, -1, +1, -1};
const int dc[] = {+0, +0, +1, -1, +1, -1, -1, +1};
const int ms[] = {+31, +29, +31, 30, +31, +30, +31, +31, +30, +31, +30, +31};
const int N = 1e3 + 5;
bool vis [N][N];
char g [N][N];
int r, c;
void dfs (int linha, int coluna, char t) {
if (linha < 0 || coluna < 0 || linha >= r || coluna >= c) return;
if (g[linha][coluna] == '*') return;
if (vis[linha][coluna]) return;
if (g[linha][coluna] == 'B' || g[linha][coluna] == 'T') if (g[linha][coluna] != t) return;
vis[linha][coluna] = true;
g[linha][coluna] = '#';
F0R (i, 4) dfs (linha + dr[i], coluna + dc[i], t);
}
bool can_reach (int linha, int coluna, char t) {
if (linha < 0 || coluna < 0 || linha >= r || coluna >= c) return false;
if (linha == 0 && coluna == 0) return true;
if (g[linha][coluna] == '*') return false;
if (vis[linha][coluna]) return false;
if (g[linha][coluna] == 'B' || g[linha][coluna] == 'T') if (g[linha][coluna] != t) return false;
vis[linha][coluna] = true;
bool ans = false;
F0R (i, 4) ans |= can_reach (linha + dr[i], coluna + dc[i], t);
return ans;
}
int main () {
ios::sync_with_stdio(0);
cin.tie(0);
cin >> r >> c;
F0R (i, r) F0R (j, c) cin >> g[i][j];
int res = 0;
while (1) {
F0R (i, r) F0R (j, c) {
if (g[i][j] == '*') continue;
if (g[i][j] == '#') continue;
memset (vis, 0, sizeof(vis));
if (can_reach (i, j, g[i][j]) == false) continue;
++res;
memset (vis, 0, sizeof(vis));
dfs (i, j, g[i][j]);
}
F0R (i, r) F0R (j, c) if (g[i][j] == 'B' || g[i][j] == 'T') goto fim;
break;
fim:;
}
cout << res << '\n';
return 0;
}
