#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(i,l,r) for(int i = (l); i < r; i++)
#define per(i,r,l) for(int i = (r); i >= l; i--)
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x).size()
#define pb push_back
#define ff first
#define ss second
const ll mod = 998244353, maxn = 800 + 5, inf = 1e18 + 5;
int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};
bool bad[maxn][maxn];
ll dist_bee[maxn][maxn], dist[maxn][maxn];
int main(){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
ll n, s; cin >> n >> s;
pair<ll, ll> st, en;
deque<pair<ll, ll>> hol;
rep(i,0,n){
rep(j,0,n){
dist_bee[i][j] = inf;
char e; cin >> e;
if(e == 'M'){
st = {i, j};
}
if(e == 'D'){
en = {i, j};
}
if(e == 'H'){
hol.push_back({i, j});
dist_bee[i][j] = 0;
}
if(e == 'H' || e == 'T') bad[i][j] = 1;
}
}
while(sz(hol)){
pair<ll, ll> p = hol.front(); hol.pop_front();
rep(d,0,4){
ll i = p.ff + dx[d], j = p.ss + dy[d];
if(i < 0 || i >= n || j < 0 || j >= n || dist_bee[i][j] != inf || bad[i][j] || pair<ll, ll>{i, j} == en) continue;
dist_bee[i][j] = dist_bee[p.ff][p.ss] + s;
hol.pb({i, j});
}
}
dist_bee[en.ff][en.ss] = inf;
auto chk = [&](ll t) -> bool{
if(dist_bee[st.ff][st.ss] <= 1LL*t*s) return 0;
rep(i,0,n){
rep(j,0,n){
dist[i][j] = inf;
}
}
dist[st.ff][st.ss] = 1LL*t*s;
deque<pair<ll, ll>> q;
q.push_back(st);
while(sz(q)){
pair<ll, ll> p = q.front(); q.pop_front();
if(p == en) return 1;
rep(d,0,4){
ll i = p.ff + dx[d], j = p.ss + dy[d];
if(i < 0 || i >= n || j < 0 || j >= n || bad[i][j]
|| dist[i][j] != inf || (dist[p.ff][p.ss] + 1) >= dist_bee[i][j]) continue;
dist[i][j] = dist[p.ff][p.ss] + 1;
q.push_back({i, j});
}
}
return 0;
};
ll l = -1, r = 1e7;
while(l + 1 < r){
ll mid = (l + r)/2;
if(chk(mid)) l = mid;
else r = mid;
}
cout << l;
return 0;
}
