#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
int ans[10][maxn];

void solve()
{
    int n;
    cin >> n;

    string a, b;
    cin >> a >> b;

    for (int i = 1; i <= 7; i++) 
        for (int j = 1; j <= n; j++)
            ans[i][j] = 0;
    
    int flag1 = 0, flag2 = 0;
    for (auto ch : a) 
        if (ch == '.') flag1 = 1;
    for (auto ch : b) 
        if (ch == '.') flag2 = 1;
        
    // cout << flag1 << flag2 << '\n';
    if (flag1 + flag2 == 1) {
        cout << "No\n";
        return;
    }
    if (flag1 + flag2 == 0) {
        cout << "Yes\n";
        for (int i = 1; i <= 7; i++) {
            for (int j = 1; j <= n; j++) {
                cout << '#';
            }
            cout << '\n';
        }
        return;
    }

    cout << "Yes\n";


    for (int i = 1; i <= n; i++) {
        if (a[i - 1] == '#') ans[1][i] = 1;
        else ans[1][i] = 0;
        if (b[i - 1] == '#') ans[7][i] = 1;
        else ans[7][i] = 0;
    }
    
    for (int i = 1; i <= n; i++) {
        ans[2][i] = 1 - ans[1][i];
        ans[6][i] = 1 - ans[7][i];
    }
    int t1, t2;
    
    for (int i = 1; i <= n - 1; i++) {
        if (ans[2][i] == 1 && ans[2][i + 1] == 0) {
            t1 = i + 1;
            ans[3][i + 1] = 1;
            break;
        }
        else if (ans[2][i] == 0 && ans[2][i + 1] == 1) {
            t1 = i;
            ans[3][i] = 1;
            break;
        }
    }
    for (int i = 1; i <= n - 1; i++) {
        if (ans[6][i] == 1 && ans[6][i + 1] == 0) {
            ans[5][i + 1] = 1;
            t2  = i + 1;
            break;
        }
        else if (ans[6][i] == 0 && ans[6][i + 1] == 1) {
            ans[5][i] = 1;
            t2  = i;
            break;
        }
    }

    // cout << t1 << " " << t2 << '\n';
    if (t1 - t2 > 1) {
        for (int i = t2 + 1; i <= t1 - 1; i++) {
            ans[4][i] = 1;
        }
    }

    else if (t2 - t1 > 1) {
        for (int i = t1 + 1; i <= t2 - 1; i++) {
            ans[4][i] = 1;
        }
    }
    else {
        ans[4][t1] = 1;
    }
    for (int i = 1; i <= 7; i++) {
        for (int j = 1; j <= n; j++) {
            if (ans[i][j] == 1) cout << '#';
            else cout << '.';
        }
        cout << '\n';
    }
    return;
}


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