#include "bits/stdc++.h"
using namespace std;
#define ii pair<ll,ll>
#define f first
#define s second
#define mp make_pair
#define ll long long
vector<ii> ways={mp(0,1),mp(1,0),mp(0,-1),mp(-1,0)};
int main(){
int N,S;
cin>>N>>S;
vector<vector<bool>> b(N,vector<bool>(N,1));
vector<vector<int>> A(N,vector<int>(N,-1));
queue<ii> QB;
int px,py,gx,gy;
string s;
for(int i=0;i<N;i++){
cin>>s;
for(int j=0;j<N;j++){
if(s[j]=='T')b[i][j]=0;
else if(s[j]=='H'){b[i][j]=0; QB.push(mp(i,j));}
else if(s[j]=='M'){px=i; py=j;}
else if(s[j]=='D'){gx=i; gy=j;}
}
}
queue<pair<ii,ii>> Q;
Q.push(mp(mp(S,0),mp(px,py)));
//f.f is step left
//f.s is t baby;
A[px][py]=1;
int T=0;
while(!Q.empty()){
int t=Q.front().f.s;
int step=Q.front().f.f;
ii curr=Q.front().s;
//cout<<curr.f<<' '<<curr.s<<'\n';
Q.pop();
if(curr.f==gx&&curr.s==gy)continue;
if(t>T){
T=t;
queue<ii> temp;
while(!QB.empty()){
ii bq=QB.front();
QB.pop();
for(auto i:ways)
if(bq.f+i.f>=0&&bq.f+i.f<N&&bq.s+i.s>=0&&bq.s+i.s<N&&b[bq.f+i.f][bq.s+i.s]){
temp.push(mp(bq.f+i.f,bq.s+i.s));
b[bq.f+i.f][bq.s+i.s]=0;
}
}
QB=temp;
}
if(step==0){step=S; t++;}
for(auto i:ways)
if(curr.f+i.f>=0&&curr.f+i.f<N&&curr.s+i.s>=0&&curr.s+i.s<N&&b[curr.f+i.f][curr.s+i.s]){
A[curr.f+i.f][curr.s+i.s]=A[curr.f][curr.s];
Q.push(mp(mp(step-1,t),mp(curr.f+i.f,curr.s+i.s)));
}
if(b[px][py]){A[px][py]++; Q.push(mp(mp(S,t+1),mp(px,py)));}
}
// for(int i=0;i<N;i++){
// for(int j=0;j<N;j++)cout<<A[i][j]<<' ';
// cout<<'\n';
// }
cout<<A[gx][gy];
}
