#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstdio>
#include <iomanip>
#include <vector>
#include <cmath>
#include <string>
#include <algorithm>
#include <queue>
#include <set>
#include <cassert>
#define inf 1e14
#define eps 1e-8
#define EPS 1e-4

using namespace std;

int n, m;


vector <vector <char> > a, b;
vector <vector <int> > g;


void build(int i) {
	for (int k = 0; k < n; ++k) {
		bool flag(false);
		for (int j = 0; j < m; ++j) {
			if (a[k][j] != b[i][j] && a[k][j] != '?') {
				flag = true;
				break;
			}
		}
		if (!flag)
			g[i].push_back(k);
	}
}


vector <int> used;
vector <int> mt;

bool try_kuhn(int v)
{
	if (used[v])
		return false;
	used[v] = 1;

	for (int i = 0; i < g[v].size(); ++i)
	{
		int to = g[v][i];
		if (mt[to] == -1 || try_kuhn(mt[to]))
		{
			mt[to] = v;
			return true;
		}
	}
	return false;

}

int main() {
	//freopen("input.txt", "r", stdin);
	freopen("lots.in", "r", stdin);
	freopen("lots.out", "w", stdout);
	while (true)
	{
		scanf("%d %d\n", &n, &m);		
		if (!n)
		{
			return 0;
		}		
		
		g.clear();
		a.assign(n, vector <char>(m));
		b.assign(n, vector <char>(m));
		g.resize(n);

		for (int i = 0; i < n; ++i){
			for (int j = 0; j < m; ++j)
				scanf("%c", &a[i][j]);
			scanf("\n");
		}
			
		scanf("\n");
		for (int i = 0; i < n; ++i){
			for (int j = 0; j < m; ++j)
				scanf("%c", &b[i][j]);
			scanf("\n");
		}		
		int w(0);
		bool flag(false);
		for (int j = 0; j < m; ++j)
			if (b[0][j] == 'x')
				w++;

		for (int i = 1; i < n; ++i) {
			int w0(0);
			for (int j = 0; j < m; ++j)
				if (b[i][j] == 'x')
					w0++;
			if (w0 > w)
				flag = true;
			else
				w = w0;
		}

		if (flag) {
			printf("NO\n");
			continue;
		}

		for (int i = 0; i < n; ++i)
			build(i);
		mt.assign(n, -1);

		/*for (int i = 0; i < n; ++i)
		{
			for (int j = 0; j < g[i].size(); ++j)
			{
				if (mt[g[i][j]] == -1)
				{
					mt[g[i][j]] = i;
					break;
				}
			}
		}*/
		for (int i = 0; i < n; ++i)
		{
			used.assign(n, false);
			try_kuhn(i);
		}

		bool f = 1;
		for (int i = 0; i < n; ++i)
		{
			if (mt[i] == -1)
			{
				printf("NO\n");
				f = 0;
				break;
			}
		}
		if (f)
		{
			printf("YES\n");
			for (int i = 0; i < n; ++i)
			{
				for (int j = 0; j < m; ++j)
				{
					printf("%c", b[mt[i]][j]);

				}
				printf("\n");
			}
		}
	}
	return 0;
}