#include <iostream>
#include <vector>
#include <string>
#include <queue>

using namespace std;

int main () {
    int H, W; cin >> H >> W;
    vector<string> G(H);
    for (int i = 0; i < H; i++) cin >> G[i];

    vector<int> size(H * W);
    vector<vector<int>> vis(H, vector<int>(W, -1));

    auto is_in = [&] (int i, int j) {
        return 0 <= i && i < H && 0 <= j && j < W;
    };
    const auto dxy = vector<pair<int, int>>{
        make_pair(0, 1),
        make_pair(1, 0),
        make_pair(0, -1),
        make_pair(-1, 0),
    };

    queue<pair<int, int>> q;
    int cur = 0;
    for (int i = 0; i < H; i++) {
        for (int j = 0; j < W; j++) {
            if (vis[i][j] != -1) continue;
            q.push(make_pair(i, j));
            vis[i][j] = cur;
            size[cur]++;

            while (!q.empty()) {
                auto pos = q.front(); q.pop();
                int y = pos.first, x = pos.second;
                for (auto& d: dxy) {
                    int ny = y + d.first, nx = x + d.second;
                    if (is_in(ny, nx) && vis[ny][nx] == -1 && G[ny][nx] == G[y][x]) {
                        vis[ny][nx] = cur;
                        size[cur]++;
                        q.push(make_pair(ny, nx));
                    }
                }
            }

            cur++;
        }
    }

    for (int i = 0; i < H; i++) {
        for (int j = 0; j < W; j++) {
            char c = G[i][j];
            if (4 <= size[vis[i][j]]) c = '.';
            cout << c;
        }
        cout << "\n";
    }
}