#include <bits/stdc++.h>
#define endl '\n'

using ll = long long;
using namespace std;

void solve(){
	int n;
	cin >> n;
	vector<string> s(7);
	for (int i = 1; i <= 5; ++i) {
		s[i].resize(n + 2);
		for (int j = 0; j <= n + 1; ++j) s[i][j] = '.';
	}
	cin >> s[0] >> s[6];
	s[0] = "." + s[0] + ".";
	s[6] = "." + s[6] + ".";
	for (int i = 1; i <= n; ++i) {
		s[1][i] = ((s[0][i] == '.') ? '#' : '.');
		s[5][i] = ((s[6][i] == '.') ? '#' : '.');
	}
	int p1 = -1, p2 = -1; 
	for (int i = 1; i <= n; ++i) {
		if (s[1][i] == '.' && (s[1][i - 1] == '#' || s[1][i + 1] == '#')) {
			s[2][i] = '#';
			p1 = i;
			break;
		}
	}
	for (int i = 1; i <= n; ++i) {
		if (s[5][i] == '.' && (s[5][i - 1] == '#' || s[5][i + 1] == '#')) {
			p2 = i;
			s[4][i] = '#';
			break;
		}
	}
	if (p1 == -1 && p2 == -1) {
		cout << "Yes" << endl; 
		for (int i = 0; i < 7; ++i) {
			cout << s[0].substr(1, n) << endl;
		}
		return;
	}
	if (p1 == -1 || p2 == -1) {
		cout << "No" << endl;
		return;
	}
	if (p1 > p2) swap(p1, p2);
	if (p2 - p1 <= 1) {
		s[3][p1] = '#';
	} else {
		for (int i = p1 + 1; i < p2; ++i) {
			s[3][i] = '#';
		}
	}
	cout << "Yes" << endl;
	for (int i = 0; i < 7; ++i) cout << s[i].substr(1, n) << endl; 
}

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    cin >> t;
    while(t--) solve();
    return 0;
}