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

int n, m, cnt;
string a, b;
char ch = 'a';
int main() {
	cin >> n >> m >> a >> b;
	for(int i = 0; i < n; i++)
		if(b[i] == '#')
			cnt++;
	cnt /= 25;
	for(int i = 0; i < n; i++) {
		if(a[i] == '#') {
			if(ch != 'a' && cnt) {
				cnt--;
				ch = 'a';
			}
			a[i] = ch;
			ch = ch == 'z' ? 'a' : ch + 1;
		}
	}
	cout << a;
	return 0;
}