#include <bits/stdc++.h>


using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;


#define int ll
#define rand shittttty_shit
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng_64(chrono::steady_clock::now().time_since_epoch().count());


typedef pair<int, int> pii;
typedef pair<string, string> pst;
typedef pair<pii, pii> piii;
typedef vector<piii> vpii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector< vi > vvi;
typedef vector< vvi > vvvi;
typedef vector<pii> vpi;
typedef vector<short> vs;
typedef vector<vs> vvs;
typedef vector<vvs> vvvs;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<ld> vld;
typedef vector<vld> vvld;
typedef vector<vvld> vvvld;
typedef vector<string> vst;
typedef vector<vst> vvst;
typedef pair<ld, ld> pld;
typedef pair<pld, pld> pldd;
typedef vector<pld> vpd;
typedef complex<double> base;


#define inmin(a, b) a = min(a, (b))
#define inmax(a, b) a = max(a, (b))
#define my_abs(a) (((a) >= 0) ? (a) : -(a))
#define mp(a, b) make_pair(a, (b))
#define ALL(a) a.begin(),a.end()
#define RALL(a) a.rbegin(),a.rend()
#define sqr(x) ((x) * (x))
#define fori(i, n) for(int i = 0; i < int(n); ++i)
#define SZ(a) ((int)((a).size()))
#define MODIK(a) (a >= M ? a - M : a)
#define triple(T) tuple<T, T, T>
#define quad(T) tuple<T, T, T, T>
#define watch(x) cout << (#x) << " = " << x << endl;
#ifdef MAX_HOME
#define cerr cout
#else
#define cerr if (false) cerr
#endif


const double PI = 2 * acos(0.0);

const string DIGITS = "0123456789";
const string ALPH = "abcdefghijklmnopqrstuvwxyz";

istream &operator >> (istream &in, pii &a)
{
    in >> a.first >> a.second;
    return in;
}


ostream &operator << (ostream &out, pii &a)
{
    out << a.first << ' ' << a.second;
    return out;
}


istream &operator >> (istream &in, pld &a)
{
    in >> a.first >> a.second;
    return in;
}


ostream &operator << (ostream &out, pld &a)
{
    out << a.first << ' ' << a.second;
    return out;
}


template <class T0, class T1>
inline ostream & operator << (ostream &out, pair<T0, T1> &a) {
    return out << "{" << a.first << ", " << a.second << "}";
}

template <class T0, class T1, class T2>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) << ", " << get<2>(a) << "}";
}

template <class T0, class T1, class T2, class T3>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2, T3> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) <<
               ", " << get<2>(a) << ", " <<  get<3>(a) << "}";
}

template<class T>
inline ostream & operator << (ostream &out, vector<T> &a) {
    out << "[";
    fori (i, a.size())
        out << a[i] << vector<string>{", ", "]  "}[i + 1 == a.size()];
    return out;
}


void print(vi kek, int k)
{
    ofstream cout("output.txt");
    cout << SZ(kek) << ' ' << k << '\n';
    for (auto p : kek) {
        cout << p << ' ';
    }
    cout.close();
    exit(0);
}


inline bool break_time(ld time)
{
    return clock() > CLOCKS_PER_SEC * time;
}


ld get_rand_ld(ld l, ld r)
{
    uniform_real_distribution<double> gen(l, r);
    return gen(rng);
}


void smain();

signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

#ifdef ART_HOME
    freopen("input.txt", "r", stdin);
    clock_t start = clock();
#endif
    cout << setprecision(4) << fixed;
    smain();
#ifdef ART_HOME
    cout << "\n\n\nTOTAL EXECUTION TIME: " << float( clock () - start ) /  CLOCKS_PER_SEC << endl;
#endif
}


const int M1 = 1000000093, p1 = 27162;
const int M2 = 1000000087, p2 = 241;


const int N = 500 + 100, B = 330, oo = 1e15 + 10, A = 26, M = 1e6 + 7, pw = 3;

int n, m;
int dp[N][N], dp1[N][N];
int used[N][N];


void dfs(int dp[N][N], int i, int j, int c)
{
    if (i < 0 || j < 0 || i >= n || j >= m || dp[i][j] == 0 || used[i][j])
        return;

    used[i][j] = c;
    dfs(dp, i - 1, j, c);
    dfs(dp, i + 1, j, c);
    dfs(dp, i, j + 1, c);
    dfs(dp, i, j - 1, c);
}


bool conect(int dp[N][N])
{
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
            used[i][j] = 0;


    int c = 1;
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
        {
            if (!used[i][j] && dp[i][j])
                dfs(dp, i, j, c++);
        }

    return c == 2;
}


void smain()
{
    cin >> n >> m;

    for (int j = 1; j + 1 < m; j += 2)
        for (int i = 1; i + 1 < n; ++i)
            dp[i][j] = 1;

    for (int j = 1; j + 1 < m; ++j)
        dp[1][j] = 1;

    for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
            dp1[i][j] = dp[i][j] ^ 1;

    for (int i = 0; i < n; ++i) {
        string s;
        cin >> s;
        int left = m, right = -1;

        for (int j = 0; j < m; ++j)
            if (s[j] == '#')
            {
                dp1[i][j] = dp[i][j] = 1;
            }
    }

    assert(conect(dp));
    assert(conect(dp1));

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (dp[i][j])
                cout << '#';
            else
                cout << '.';
        }

        cout << '\n';
    }

    cout << '\n';

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (dp1[i][j])
                cout << '#';
            else
                cout << '.';
        }

        cout << '\n';
    }
}

Measured memory_bytes: 28416