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

using ll = long long;

signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    int n, m;
    cin >> n >> m;
    vector<string> s(n + 2);
    for(int i = 0; i <= n + 1; i++) {
        cin >> s[i];
    }
    vector fr(n + 2, vector(m + 2, vector<int>()));
    queue<array<int, 4>> q; // <x, y, val, dir>
    // 0: up  1: right  2: down  3: left
    for(int i = 1; i <= n; i++) {
        if(s[i][0] != '.') q.push({i, 1, s[i][0], 3});
        if(s[i][m + 1] != '.') q.push({i, m, s[i][m + 1], 1});
    }
    for(int i = 1; i <= m; i++) {
        if(s[0][i] != '.') q.push({1, i, s[0][i], 0});
        if(s[n + 1][i] != '.') q.push({n, i, s[n + 1][i], 2});
    }
    constexpr int dx[] = {1, 0, -1, 0}, dy[] = {0, -1, 0, 11};
    while(q.size()) {
        auto [x, y, val, dir] = q.front();
        q.pop();
        if(x < 1 || x > n || y < 1 || y > m) {
            cout << "NO\n";
            return 0;
        }
        if(s[x][y] == '.') {
            s[x][y] = val, fr[x][y].push_back(dir);
        } else if(s[x][y] == 'x') {
            q.push({x + dx[dir], y + dy[dir], val, dir});
        } else if(s[x][y] != val) {
            q.push({x + dx[dir], y + dy[dir], val, dir});
            for(auto i : fr[x][y]) {
                q.push({x + dx[i], y + dy[i], val, i});
            }
            s[x][y] = 'x';
        } else {
            fr[x][y].push_back(dir);
        }
    }
    cout << "YES\n";
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            if(s[i][j] == 'x') s[i][j] = '.';
            cout << s[i][j];
        }
        cout << '\n';
    }
    return 0;
}