#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
ll n, s;
cin >> n>> s;
vector<vector<char> > grid(n, vector<char>(n));
queue<pair<ll ,ll> > q1;
queue<pair<ll ,ll> > q2;
pair<ll ,ll> home;
pair<ll ,ll> start;
vector<vector<ll> > hdist(n, vector<ll>(n, -1));
for (ll i = 0; i < n; i++) for (ll j = 0; j < n; j++) {
cin >> grid[i][j];
if (grid[i][j] == 'H') {
q1.push({i, j});
hdist[i][j] = 0;
}
else if (grid[i][j] == 'M') {
// q2.push({i, j});
start = {i, j};
}
else if (grid[i][j] == 'D') home = {i, j};
}
vector<ll> dx = {1, -1, 0, 0};
vector<ll> dy = {0, 0, -1, 1};
while (!q1.empty() && hdist[home.first][home.second] == -1) {
pair<ll, ll> curr = q1.front();
q1.pop();
for (ll i = 0; i < 4; i++) {
ll x = curr.first + dx[i];
ll y = curr.second + dy[i];
if (x >= 0 && x < n && y >= 0 && y < n) {
if (hdist[x][y] == -1 && (grid[x][y] == 'G' || grid[x][y] == 'D')) {
hdist[x][y] = hdist[curr.first][curr.second] + s;
q1.push({x, y});
}
}
}
}
vector<vector<pair<ll, ll> > > parent(n, vector<pair<ll, ll> >(n, {-1, -1}));
ll hi = n*n;
ll lo = 0;
while (hi > lo || (hi == 0 && lo == 0)) {
ll mid = (hi + lo + 1)/2;
// cout << hi << lo << endl;
vector<vector<ll> > mdist(n, vector<ll>(n, -1));
mdist[start.first][start.second] = mid * s;
q2.push(start);
// cout << hdist[3][1] << endl;
while (!q2.empty()) {
pair<ll, ll> curr = q2.front();
// cout << mdist[curr.first][curr.second] << endl;
q2.pop();
for (ll i = 0; i < 4; i++) {
ll x = curr.first + dx[i];
ll y = curr.second + dy[i];
if (x >= 0 && x < n && y >= 0 && y < n) {
if (mdist[x][y] == -1 && (grid[x][y] == 'G' || grid[x][y] == 'D') && (hdist[x][y] > mdist[curr.first][curr.second] + 1 || hdist[x][y ] == -1)) {
mdist[x][y] = mdist[curr.first][curr.second] + 1;
q2.push({x, y});
parent[x][y] = {curr.first, curr.second};
}
}
}
}
if (mdist[home.first][home.second] != -1) {
lo = mid;
if (hi == 0 && lo == 0) break;
} else {
hi = mid - 1;
}
}
// ll ans = 100000000;
// pair<ll ,ll> current = home;
// // cout << mdist[home.first][home.second] << endl;
// if (mdist[home.first][home.second] == -1) {
// cout << -1 << endl;
// return 0;
// }
// while (current != start) {
// ll x = current.first;
// ll y = current.second;
// if (hdist[x][y] != -1) {
// // cout << x << y << hdist[x][y] << endl;
// ans = min(ans, hdist[x][y]-mdist[x][y]);
// }
// current = parent[x][y];
// }
// for (ll i = 0; i < 4; i++) {
// ll x = home.first + dx[i];
// ll y = home.second + dy[i];
// if (x >= 0 && x < n && y >= 0 && y < n && grid[x][y] != 'T') {
// ans = max(hdist[x][y] - mdist[x][y], ans);
// cout << mdist[x][y] << hdist[x][y] << x << y << endl;
// }
// }
cout << hi << endl;
}
