#include<bits/stdc++.h>
#define fo(i,a,b) for (ll (i)=(a);(i)<=(b);(i)++)
#define ll long long 
#define db long double 
using namespace std;
const int N = 5e5 + 10;
const int mo = 998244353;
string s, t, ans[10];
int n;
void solve() {
    cin >> n >> s >> t;
    s = " " + s;
    t = " " + t;
    fo(i, 1, 7) ans[i].resize(n+1);
    int f1 = 1, f2 = 1;
    fo(i, 1, n) {
        if (s[i] == '.') f1 = 0;
        if (t[i] == '.') f2 = 0;
    }
    if (f1 && f2) {
        cout << "Yes\n";
        fo(i, 1, 7) {
            fo(j, 1, n) cout << "#";
            cout << "\n";
        }
        return;
    }
    if (f1 != f2) {
        cout << "No\n";
        return;
    }
    

    fo(i, 1, n) {
        ans[1][i] = s[i];
        ans[7][i] = t[i];
    }

    fo(i, 1, n) {
        if (s[i] == '.') ans[2][i] = '#';
        else ans[2][i] = '.';

        if (t[i] == '.') ans[6][i] = '#';
        else ans[6][i] = '.';
    }

    int l, r;
    fo(i, 1, n) {
        if (ans[2][i] == '.') {
            if (i < n && ans[2][i + 1] == '#') {
                l = i;break;
            }
            if (i > 1 && ans[2][i - 1] == '#') {
                l = i;break;
            }
        }
    }
    fo(i, 1, n) {
        if (ans[6][i] == '.') {
            if (i < n && ans[6][i + 1] == '#') {
                r = i;break;
            }
            if (i > 1 && ans[6][i - 1] == '#') {
                r = i;break;
            }
        }
    }
    fo(i, 3, 5) {
        fo(j, 1, n) ans[i][j] = '.';
    }
    // cout << l << " " << r << "\n";
    if (l == r) {
        ans[3][l] = ans[4][l] = ans[5][l] = '#';
    }
    else if (abs(r - l) == 1) {
        ans[3][l] = ans[4][l] = ans[5][r] = '#';
    }
    else {
        ans[3][l] = ans[5][r] = '#';
        fo(j, min(l,r)+ 1, max(l,r) - 1) ans[4][j] = '#';
    }
    cout << "Yes\n";
    fo(i, 1, 7) {
        fo(j, 1, n) cout << ans[i][j];
        cout << "\n";
    }
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int T = 1;
    cin >> T;
    while (T--) solve();
    return 0;
}