#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define fi first
#define se second
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
const ll MOD1000000007 = 1000000007;
const ll MOD998244353 = 998244353;
const ll MOD[3] = {999727999, 1070777777, 1000000007};
const ll LINF = 1LL << 60LL;
const int IINF = (1 << 30) - 2;


struct union_find{
    vector<int> par;
    vector<int> siz;
    
    union_find(int n) : par(n), siz(n, 1){
        for(int i=0; i<n; i++) par[i] = i;
    }
    
    int root(int x){
        if (par[x] == x) return x;
        return par[x] = root(par[x]);
    }
 
    void unite(int x, int y){
        int rx = root(x);
        int ry = root(y);
        if (rx == ry) return;
        if (siz[rx] < siz[ry]) swap(rx, ry);
        siz[rx] += siz[ry];
        par[ry] = rx;
    }
 
    bool same(int x, int y){
        int rx = root(x);
        int ry = root(y);
        return rx == ry;
    }
 
    int size(int x){
        return siz[root(x)];
    }
};


void solve(){
    int h, w; cin >> h >> w;
    vector<vector<char>> s(h, vector<char>(w));
    for(int i=0; i<h; i++)for(int j=0; j<w; j++) cin >> s[i][j];

    int di[4] = {0, 0, 1, -1}, dj[4] = {1, -1, 0, 0};
    union_find uf(h*w);
    for(int i=0; i<h; i++)for(int j=0; j<w; j++)for(int k=0; k<4; k++){
        int ni = i + di[k], nj = j + dj[k];
        if(ni<0||nj<0||h<=ni||w<=nj) continue;
        if(s[i][j]!=s[ni][nj]) continue; 
        uf.unite(i*w+j, ni*w+nj);
    }

    for(int i=0; i<h; i++){
        for(int j=0; j<w; j++){
            if(uf.size(i*w+j)>=4) s[i][j] = '.';
            cout << s[i][j];
        }
        cout << '\n';
    }
}

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    
    int T=1;
    //cin >> T;
    while(T--) solve();
}