#include <bits/stdc++.h>
using namespace std;
// types - only for stuff used a lot
using ll = long long;
#define vv vector
#define Pp pair
// IO
#define get(x) scanf("%d",&x)
#define getl(x) scanf("%lld",&x);
// Operations
#define pb push_back
#define pob pop_back
#define sz(a) int(a.size())
#define re(a,b) a=max(a,b) // relax
#define ri(a,b) a=min(a,b) // relaxi
// Debugging
#ifndef LOCAL
#define cerr if (0) cerr
#else
#define cerr cout
#endif
#define print(arr,n) {for (int _ = 0; _ < n; _++) cerr<<arr[_]<<" "; cerr << endl; }
#define printv(vec) {for (int _ : vec) cerr<<_<<" "; cerr<<endl;}
const int mod = 1e9+7, oo = 1e9;
const ll loo = 1e18;
// Functions
ll modpow(ll a, ll b) {
ll ans = 1; // faster modpow than recursive
for (; b; b/=2,a=a*a%mod)
if (b&1) ans = (ans*a)%mod;
return ans;
}
ll gcd(ll a, ll b) {
while (a) b%=a,swap(a,b);
return b;
}
#define bitcount __builtin_popcountll
#define f(i,a,b) for (int i = a; i < b; i++)
#define fr(i,a,b) for (int i = b-1; i >= a; i--)
/*
ALRIGHT HACKERS, THIS IS WHERE THE ACTUAL CODE BEGINS
*/
const bool DEBUG = 1;
using pii = pair<int,int>;
#define IN(i,a,b) (a<=i&&i<=b)
const int N = 1000;
int n,s;
vector<pii> bees;
bool wall[N][N],visR[N][N],visB[N][N];
pii st, fin;
int di[] = {1,-1,0,0};
int dj[] = {0,0,1,-1};
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
#ifdef LOCAL
if (DEBUG) freopen("input.txt", "r", stdin);
if (DEBUG) freopen("output.txt", "w", stdout);
clock_t start = clock();
#endif
cin>>n>>s;
f(i,0,n) f(j,0,n) wall[i][j] = 0;
f(i,0,n) f(j,0,n) {
char c; cin>>c;
if (c == 'T')
wall[i][j] = 1;
else if (c == 'M')
st = {i,j};
else if (c == 'D')
fin = {i,j};
else if (c == 'H')
bees.pb({i,j});
}
int lo = 0, hi = N*N*2;
auto valid = [&](int i, int j) {
return IN(i,0,n-1) && IN(j,0,n-1) && !wall[i][j] && !visR[i][j];
};
auto fu = [&](int T) {
f(i,0,n) f(j,0,n) visB[i][j] = visR[i][j] = 0;
vector<pii> bear, bee;
bear.pb(st);
visB[st.first][st.second] = 1;
for (pii b : bees) {
bee.pb(b);
visR[b.first][b.second] = 1;
}
while (bear.size()||bee.size()) {
// bear gets to move first
if (T--<=0) { // eat for T rounds
f(_,0,s) {
vector<pii> nxt;
for (pii pp : bear) {
int i = pp.first, j = pp.second;
if (visR[i][j])
continue;
f(k,0,4) {
int ni = i+di[k], nj = j+dj[k];
if (valid(ni,nj) && !visB[ni][nj]) {
visB[ni][nj] = 1;
nxt.pb({ni,nj});
}
}
}
bear = nxt;
}
}
// then bee move
vector<pii> nxt;
for (pii pp : bee) {
int i = pp.first, j = pp.second;
f(k,0,4) {
int ni = i+di[k], nj = j+dj[k];
if (valid(ni,nj) && pii(ni,nj) != fin) {
visR[ni][nj] = 1;
nxt.pb({ni,nj});
}
}
}
bee = nxt;
}
return visB[fin.first][fin.second];
};
while (lo<=hi) {
int mid = lo+hi>>1;
if (fu(mid))
lo = mid+1;
else
hi = mid-1;
}
cout << hi << endl;
#ifdef LOCAL
cout << setprecision(12) << (long double)(clock()-start) / CLOCKS_PER_SEC << endl;
#endif
return 0;
}
