#include<bits/stdc++.h>

#define ll  long long
#define ull unsigned long long
#define ld long double
#define pii pair<ll,ll>
using namespace std;
#pragma GCC optimize(3)
#define N 1005
ll a[N][N],b[N][N];
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    // freopen("")
    ll n, m;
    cin >> n >> m;
    string s;
    for (int i = 0; i < n; i++) {
        cin >> s;
        for (int j = 0; j < m; j++) {
            if (s[j] == 'X') a[i][j] = 1;
        }
    }
 //   cerr<<1;
    for (int i = 0; i < n; i++) {
        cin >> s;
        for (int j = 0; j < m; j++) {
            if (s[j] == 'X') b[i][j] = 1;
        }
    }
 //   cerr<<2;
    ll cnt = 0;
    for (int i = 0; i < n; i++) {
        //cin >> s;
        for (int j = 0; j < m; j++) {
            if (a[i][j] ^ b[i][j]) cnt++;
        }
    }
    if (cnt > (m * n) / 2) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                if (a[i][j] == 1) {
                    cout << '.';
                } else {
                    cout << 'X';
                }
            }
            cout << endl;
        }
    } else {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                if (a[i][j] == 1) {
                    cout << 'X';
                } else {
                    cout << '.';
                }
            }
            cout << endl;
        }
    }
    return 0;
}