#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define f first
#define s second
#define pr pair<int, int>
#define pb push_back
const int ndim=800;
const int dmax=1e9;
vector<string> mp(ndim);
vector<int> level(ndim*ndim, -1);
vector<int> level2(ndim*ndim, -1);
int dx[4]={1, -1, 0, 0};
int dy[4]={0, 0, 1, -1};
int n, s;
bool dmcheck(int x, int y){
if(x>=0 && x<n && y>=0 && y<n && mp[x][y]!='T' && mp[x][y]!='D' && level[x*n+y]==-1 ) return true;
else return false;
}
bool bearcheck(int x, int y){
if(x>=0 && x<n && y>=0 && y<n && mp[x][y]!='T' && mp[x][y]!='H' && level2[x*n+y]==-1 ) return true;
else return false;
}
bool check(int mid, pr M, pr hs){
for (int i=0; i<n*n; i++) level2[i]=-1;
queue<pr> q;
q.push({M.f*n+M.s, 0});
level2[M.f*n+M.s]=0;
bool judge=false;
while(!q.empty()){
pr n1=q.front(); q.pop();
int nd=n1.f; int lev=n1.s;
int x=nd/n; int y=nd%n;
//cout<< "x/y= "<<x<<" "<<y<<endl;
//cout<<" level[x*n+y]-mid= "<<level[x*n+y]-mid<<endl;
if(lev>=(level[x*n+y]-mid)*s) continue;
for (int i=0; i<4; i++){
int x2=x+dx[i]; int y2=y+dy[i];
if( bearcheck(x2, y2)){
//cout<<" x2/y2= "<<x2<<" "<<y2<< "hs= "<<hs.f<<" "<<hs.s<<endl;
if(x2==hs.f && y2==hs.s ){ judge=true; break;}
//cout<<" lev+1 / (level[x2*n+y2]-mid)*s= "<<lev+1 <<" "<< (level[x2*n+y2]-mid)*s<<endl;
if(lev+1 <= (level[x2*n+y2]-mid)*s){ // level is bee
q.push({x2*n+y2, lev+1});
level2[x2*n+y2]= lev+1;
}
}
if(judge) break;
}
if(judge) break;
}
//for (int i=0; i<n; i++){
// for (int j=0; j<n; j++) cout<<level2[i*n+j]<<" ";
// cout<<endl;
//}
//cout<<" judge= "<<judge<<endl;
return judge;
}
int main(){
cin>>n>>s;
vector<pr> hv;
pr M, hs;
for (int i=0; i<n; i++) {
cin>>mp[i];
for (int j=0; j<n; j++){
if(mp[i][j]=='H') hv.pb({i, j});
if(mp[i][j]=='M') M={i, j};
if(mp[i][j]=='D') hs={i, j};
}
}
//cout<<" hs= "<<hs.f<<" "<<hs.s<<endl;
queue<pr> q;
for (auto elem: hv) {
q.push({elem.f*n+elem.s, 0});
level[elem.f*n+elem.s]=0;
}
while (!q.empty()){
pr n1=q.front(); q.pop();
int nd=n1.f; int lev=n1.s;
int x=nd/n; int y=nd%n;
for (int i=0; i<4; i++){
int x2=x+dx[i]; int y2=y+dy[i];
if(dmcheck(x2, y2)){
q.push({x2*n+y2, lev+1}); level[x2*n+y2]=lev+1;
}
}
}
//for (int i=0; i<n; i++){
// for (int j=0; j<n; j++) cout<<level[i*n+j]<<" ";
// cout<<endl;
//}
int lft=0; int rht=100000;
while(lft<rht ){
int mid=(rht+lft+1)/2;
// cout<<" lft/rht/mid= "<<lft<<" "<<rht<<" "<<mid<<endl;
if(check(mid, M, hs)) lft=mid;
else rht=mid-1;
}
cout<<lft<<endl;
}
