#include <bits/stdc++.h>
using namespace std;

ifstream fin("barbar.in");
ofstream fout("barbar.out");
const int oo = 1e9;
queue<pair <int, int> > q;
char a[1005][1005], s[1005];
int m, n;
int b[1005][1005];
int dx[] = {-1, 1, 0, 0};
int dy[] = {0, 0, -1, 1};
void Read()
{
    fin >> n >> m;
    fin.get();
    for (int i = 1; i <= n; i++)
    {
        fin.getline(s, 1004);
        for (int j = 0; j <= m; j++)
            a[i][j + 1] = s[j];
    }
}
void Display()
{
    int i, j;
    for (i = 1; i <= n; i++, cout << "\n")
        for (j = 1; j <= m; j++)
            cout << a[i][j] << " ";
}
void Init()
{
    int i, j;
    for(i = 1; i <= n; i++)
        for (j = 1; j <= m; j++)
            if (a[i][j] == 'D')
                b[i][j] = 0;
            else b[i][j] = oo;
}
void Bord()
{
    for (int i = 0; i <= n + 1; i++)
        a[i][0] = a[i][m + 1] = 'Z';
    for (int j = 0; j <= m; j++)
        a[0][j] =a[n + 1][j] = 'Z';
}
void Lee(int i, int j)
{
    int x, y, p;
    q.push({i, j});
    /// D->A->T
    while(!q.empty())
    {
        i = q.front().first;
        j = q.front().second;
        q.pop();
        for (p = 0; p < 4; p++)
        {
            x = i + dx[p];
            y = j + dy[p];
            if (a[x][y] != 'Z' && b[x][y] > b[i][j] + 1)
            {
                b[x][y] = b[i][j] + 1;
                q.push({i, j});
            }
        }
    }
}
void Solve()
{
    int i, j;
    for (i = 1; i <= n; i++)
        for (j = 1; j <= m; j++)
        {
            if (a[i][j] == 'D')
            {
                Init();
            }
        }
}
int main()
{
    Read();
    Init();
    Bord();
    return 0;
}