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

#define V vector
#define pb push_back

typedef long long LL;

const int mod = 998244353;

V<string> gen(string s) {
    int n = s.size();
    string p = s;
    for(char &c : p) {
        if(c == '.') c = '#';
        else c = '.';
    }
    string q(n, '.');
    q[0] = '#';

    if(p[0] == p[1] && p[1] == '#') {
        p[0] = '.';
    } else if(p[0] == '#' && p[1] == '.') {
        
    } else if(p[0] == '.' && p[1] == '#') {

    } else if(p[0] == '.' && p[1] == '.') {
        q[0] = '.';
        int pos;
        for(int i = 0; i < n; i++) {
            if(p[i] == '#') {
                pos = i;
                break;
            }
        }
        for(int i = 1; i < pos; i++) q[i] = '#';
    }
    return {s, p, q};
}

bool all_sharp(string s) {
    bool ok = 1;
    for(auto c : s) {
        if(c != '#') ok = 0;
    }
    return ok;
}
bool all_dot(string s) {
    bool ok = 1;
    for(auto c : s) {
        if(c != '.') ok = 0;
    }
    return ok;
}

void solve() {
    int n; cin >> n;
    string a, b; cin >> a >> b;

    if(all_dot(a) && all_sharp(b) || all_dot(b) && all_sharp(a)) {
        cout << "Yes" << "\n";
        for(int i = 1; i <= 6; i++) cout << a << "\n";
        cout << b << "\n";
        return;
    }
    if(all_sharp(a) ^ all_sharp(b)) {
        cout << "No" << "\n";
        return;
    }
    cout << "Yes" << "\n";
    if(all_sharp(a) && all_sharp(b)) {
        for(int i = 1; i <= 7; i++) {
            cout << a << "\n";
        }
        return;
    }

    auto va = gen(a), vb = gen(b);
    for(int i = 0; i < 3; i++) cout << va[i] << "\n";
    cout << "#";
    for(int i = 2; i <= n; i++) cout << ".";
    cout << "\n";
    for(int i = 2; i >= 0; i--) cout << vb[i] << "\n";

}

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int t; cin >> t;
    while(t--)
        solve();
}