#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pi pair<int, int>
#define ti tuple<int, int, int>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
vector<vector<char>> grid;
vector<vector<ll>> t;
vector<pi> direction={{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
int n;
ll s;
int si=-1, sj=-1;
bool bfs(ll mid) {
vector<vector<ll>> step(n, vector<ll>(n, -1));
queue<pi> nq;
step[si][sj]=s*mid;
nq.push({si, sj});
while(nq.size()) {
auto [i, j]=nq.front(); nq.pop();
if(grid[i][j]=='D') return true;
for(auto &[di, dj]: direction) {
int ni=i+di;
int nj=j+dj;
if(ni>=0 && nj>=0 && ni<n && nj<n && step[i][j]+1<1LL*s*t[ni][nj] && grid[ni][nj]!='T' && step[ni][nj]==-1) {
step[ni][nj]=step[i][j]+1;
nq.push({ni, nj});
}
}
}
return false;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n >> s;
grid.resize(n, vector<char>(n));
t.resize(n, vector<ll>(n, INT_MAX));
queue<pi> q;
for(int i=0; i<n; i++) {
for(int j=0; j<n; j++) {
cin >> grid[i][j];
if(grid[i][j]=='H') {
q.push({i, j});
t[i][j]=0;
} else if(grid[i][j]=='M') {
si=i;
sj=j;
}
}
}
while(q.size()) {
auto [i, j]=q.front(); q.pop();
for(auto &[di, dj]: direction) {
int ni=i+di;
int nj=j+dj;
if(ni>=0 && nj>=0 && ni<n && nj<n && t[ni][nj]==INT_MAX && grid[ni][nj]!='T') {
t[ni][nj]=t[i][j]+1;
q.push({ni, nj});
}
}
}
// for(int i=0; i<n; i++) {
// for(int j=0; j<n; j++) {
// if(t[i][j]==INT_MAX) cout << "- ";
// else cout << t[i][j] << " ";
// }
// cout << '\n';
// }
ll l=-1, r=INT_MAX;
while(l<r) {
ll mid=(l+r+1)/2;
if(bfs(mid)) {
l=mid;
} else {
r=mid-1;
}
}
cout << l;
return 0;
}
