#include <bits/stdc++.h>
using namespace std;
#define int long long
#define de(a) cout << #a << " = " << a << "\n"
#define deg(a) cout << #a << " = " << a << " "
const long double pi = acosl(-1);
constexpr long double eps = 1e-12;
constexpr long long inf = 0x3f3f3f3f3f3f3f3f;
constexpr int mod = 998244353;
constexpr int N = 1e6 + 10;
constexpr int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};
unsigned long long a[N], b[N];

void solve() {
    int n;
    cin >> n;
    string s1, s7;
    cin >> s1 >> s7;

    if (s1 == string(n, '#') && s7 == string(n, '#')) {
        cout << "Yes\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        cout << s1 << "\n";
        return;
    } else if (s1 == string(n, '#') || s7 == string(n, '#')) {
        cout << "No\n";
        return;
    }

    string s2, s6;
    for (int i = 0; i < n; i++) {
        s2 += (s1[i] == '#' ? '.' : '#');
        s6 += (s7[i] == '#' ? '.' : '#');
    }

    string s3(n, '.'), s4(n, '.'), s5(n, '.');
    int l, r;
    for (int i = 0; i + 1 < n; i++) {
        if (s2[i] != s2[i + 1]) {
            if (s2[i] == '#') {
                s3[i + 1] = '#';
                l = i + 1;
            } else {
                s3[i] = '#';
                l = i;
            }
            break;
        }
    }
    for (int i = 0; i + 1 < n; i++) {
        if (s6[i] != s6[i + 1]) {
            if (s6[i] == '#') {
                s5[i + 1] = '#';
                r = i + 1;
            } else {
                s5[i] = '#';
                r = i;
            }
            break;
        }
    }

    if (l > r) {
        swap(l, r);
    }

    if (r - l <= 1) {
        s4 = s3;
    } else {
        for (int i = l + 1; i <= r - 1; i++) {
            s4[i] = '#';
        }
    }

    cout << "Yes\n";
    cout << s1 << "\n";
    cout << s2 << "\n";
    cout << s3 << "\n";
    cout << s4 << "\n";
    cout << s5 << "\n";
    cout << s6 << "\n";
    cout << s7 << "\n";
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);

    int T = 1;
    cin >> T, cin.get();
    while (T--) {
        solve();
    }

    return 0;
}