#include<bits/stdc++.h>
#define ll long long
#define mp make_pair
#define pub push_back
#define pob pop_back
#define ss second
#define ff first
#define ext exit(0)
using namespace std;
int n,s,l,r,x,y,zu[801][801],bo[801][801],ax,ay,h[4]={0,0,-1,1},v[4]={-1,1,0,0};
char c[801][801];
void dfs(int i, int j){
queue<pair<pair<int,int>,int> >q;
memset(bo,0,sizeof bo);
q.push(mp(mp(i,j),0));
bo[i][j]=1;
zu[i][j]=0;
while(!q.empty()){
int ii=q.front().ff.ff,jj=q.front().ff.ss,zz=q.front().ss;
for(int k=0;k<4;k++){
if(ii+h[k]<=n && ii+h[k]>0 && jj+v[k]<=n && jj+v[k]>0 && c[ii+h[k]][jj+v[k]]!='T' && c[ii+h[k]][jj+v[k]]!='D' && !bo[ii+h[k]][jj+v[k]] && zu[ii+h[k]][jj+v[k]]>zz+1){
bo[ii+h[k]][jj+v[k]]=1;
zu[ii+h[k]][jj+v[k]]=zz+1;
q.push(mp(mp(ii+h[k],jj+v[k]),zz+1));
}
}
q.pop();
}
}
bool can(int k){
queue<pair<pair<int,int>,pair<int,int> > >q;
memset(bo,0,sizeof bo);
q.push(mp(mp(x,y),mp(k,0)));
bo[x][y]=1;
while(!q.empty()){
int xx=q.front().ff.ff,yy=q.front().ff.ss,kk=q.front().ss.ff,zz=q.front().ss.ss;
if(zz==s) zz=1,kk++;
else zz++;
for(int i=0;i<4;i++){
if(bo[ax][ay]) return 1;
if(xx+h[i]>0 && xx+h[i]<=n && yy+v[i]>0 && yy+v[i]<=n && c[xx+h[i]][yy+v[i]]!='T' && !bo[xx+h[i]][yy+v[i]] && zu[xx+h[i]][yy+v[i]]>kk){
bo[xx+h[i]][yy+v[i]]=1;
q.push(mp(mp(xx+h[i],yy+v[i]),mp(kk,zz)));
}
}
q.pop();
}
return 0;
}
int main (){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n>>s;
for(int i=1;i<=n;i++){
for(int j=1;j<=n;j++){
cin>>c[i][j];
if(c[i][j]=='M') x=i,y=j;
if(c[i][j]=='D') ax=i,ay=j;
zu[i][j]=1e9;
}
}
for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) if(c[i][j]=='H') dfs(i,j);
l=0,r=640000;
while(l+1<r){
ll mid=(l+r)/2;
if(can(mid)) l=mid;
else r=mid;
}
cout<<l;
}
