#include <bits/stdc++.h>
#define Y8o "main"
#define maxn (int) 805
#define ll long long
#define pii pair<int, int>
#define gb(i, j) ((i >> j) & 1)
#define all(x) x.begin(), x.end()
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define f first
#define s second
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll GetRandom(ll l, ll r) {
return uniform_int_distribution<ll> (l, r) (rng);
}
void iof() {
if(fopen(Y8o".inp", "r"))
{
freopen(Y8o".inp", "r", stdin);
// freopen(Y8o".out", "w", stdout);
}
ios_base::sync_with_stdio(0);
cin.tie(NULL), cout.tie(NULL);
}
void ctime() {
cerr << "\n" << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
}
int n, S;
pii st, en;
char a[maxn][maxn];
int lim[maxn][maxn], dp[maxn][maxn];
int dx[] = { 1, -1, 0, 0 };
int dy[] = { 0, 0, -1, 1 };
bool exist(int u, int v) { return 1 <= u && u <= n && 1 <= v && v <= n && a[u][v] != 'T'; }
bool check(int tg) {
for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++)
dp[i][j] = 1e9;
dp[st.f][st.s] = tg * S;
queue<pii> q;
q.push(st);
while(q.size()) {
int i, j; tie(i, j) = q.front();
q.pop();
for(int t = 0; t <= 3; t ++) {
int u = i + dx[t], v = j + dy[t];
if(exist(u, v) && dp[i][j] + 1 < lim[u][v]) {
dp[u][v] = dp[i][j] + 1;
q.push({ u, v });
}
}
}
return dp[en.f][en.s] < lim[en.f][en.s];
}
void solve() {
cin >> n >> S;
for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) {
cin >> a[i][j];
if(a[i][j] == 'M') st = {i, j};
else if(a[i][j] == 'D') en = {i, j};
}
queue<pii> q;
for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) {
lim[i][j] = 1e9;
if(a[i][j] == 'H') lim[i][j] = 0, q.push({ i, j });
}
while(q.size()) {
int i, j; tie(i, j) = q.front();
q.pop();
for(int t = 0; t <= 3; t ++) {
int u = i + dx[t], v = j + dy[t];
if(exist(u, v)) {
if(lim[u][v] > lim[i][j] + S) {
lim[u][v] = lim[i][j] + S;
q.push({ u, v });
}
}
}
}
int l = 1, r = n * n;
while(l <= r) {
int mid = (l + r) >> 1;
if(check(mid)) l = mid + 1;
else r = mid - 1;
}
cout << r;
}
int main() {
iof();
int nTest = 1;
// cin >> nTest;
while(nTest --) {
solve();
}
ctime();
return 0;
}
