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

ll n, m;
vector<vector<char>> grid;
vector<vector<ll>> vis;

ll cox[8] = {1, -1, 0, 0, 1, 1, -1, -1};
ll coy[8] = {0, 0, -1, 1, 1, -1, 1, -1};

bool ok(ll nx, ll ny) {
    return (nx >= 0 && nx < n && ny >= 0 && ny < m && !vis[nx][ny]);
}

ll mx = 0, cnt = 0;

void dfs(ll x, ll y) {
    vis[x][y] = 1;
    cnt++;
    mx = max(mx, cnt);

    for (int i = 0; i < 8; i++) {
        ll nx = x + cox[i];
        ll ny = y + coy[i];
        char ch = grid[x][y] + 1;

        if (ok(nx, ny) && grid[nx][ny] == ch) {
            dfs(nx, ny);
        }
    }
    cnt--;
}

int main() {
    int case_num = 1;

    while (true) {
        cin >> n >> m;
        if (n == 0 && m == 0) break;

        vis.assign(n, vector<ll>(m, 0));
        grid.assign(n, vector<char>(m));
        mx = 0;

        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                cin >> grid[i][j];

        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                if (!vis[i][j] && grid[i][j] == 'A') {
                    cnt = 0;
                    dfs(i, j);
                }
            }
        }

        cout << "Case " << case_num << ": " << mx << "\n";
        case_num++;
    }

    return 0;
}