#include <bits/stdc++.h>
using namespace std;
#define all(v) v.begin(),v.end()
#define eb emplace_back
#define ll long long
#define fi first
#define se second
int t,n,i,m,j,x,y,X,Y;
const int maxn= 8e2 + 10;
int di[4] = {1,0,-1,0},dj[4] = {0,1,0,-1};
char ch[maxn][maxn];
pair<int,int> b[maxn][maxn],bb[maxn][maxn];
queue<pair<int,int>> q;
bool check(int i,int j)
{
return i >= 0 && j >= 0 && i < n && j < n;
}
pair<int,int> cal(pair<int,int> tmp)
{
tmp.se++;
tmp.fi += tmp.se/m;
tmp.se %= m;
return tmp;
}
bool solve(int tmp)
{
for(i = 0;i<n;i++)
{
for(j = 0;j<n;j++)
{
bb[i][j] = b[i][j];
}
}
queue<pair<int,int>> q;
q.push({x,y});
bb[x][y] = {tmp,0};
while(q.size())
{
i = q.front().fi;
j = q.front().se;
q.pop();
for(int k = 0;k<4;k++)
{
int I = i + di[k],J = j + dj[k];
if(check(I,J) && bb[I][J] > cal(bb[i][j]))
{
bb[I][J] = cal(bb[i][j]);
q.push({I,J});
}
}
}
// for(i = 0;i<n;i++)
// {
// for(j = 0;j<n;j++)
// {
// cout<<bb[i][j].fi * (abs(bb[i][j].fi) != 1e8)<<'-'<<bb[i][j].se<<" ";
// }
// cout<<'\n';
// }
// cout<<'\n';
return bb[X][Y].fi != 1e8;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cin>>n>>m;
m++;
for(i = 0;i<n;i++)
{
for(j = 0;j<n;j++)
{
cin>>ch[i][j];
if(ch[i][j] == 'H')q.push({i,j});
if(ch[i][j] == 'M')
{
x = i,y = j;
}
if(ch[i][j] == 'D')
{
X = i,Y = j;
}
if(ch[i][j] == 'T' || ch[i][j] == 'H')
{
if(ch[i][j] == 'T')b[i][j].fi = -1e8;
}
else b[i][j].fi = 1e8;
}
}
while(q.size())
{
i = q.front().fi;
j = q.front().se;
q.pop();
for(int k = 0;k<4;k++)
{
int I = i + di[k],J = j + dj[k];
if(check(I,J) && ch[I][J] != 'M' && ch[I][J] != 'D' && b[I][J].fi > b[i][j].fi +1)
{
b[I][J].fi = b[i][j].fi +1;
q.push({I,J});
}
}
}
int l = -1,r = 1e7,mid;
while(l < r)
{
mid = (l + r + 1)/2;
if(solve(mid))l = mid;
else r = mid - 1;
}
cout<<l;
return 0;
}
