#include <bits/stdc++.h>

using i64 = long long;

void solve(){
    int n;
    std::cin >> n;
    std::vector<std::string> mp(7);
    std::cin >> mp[0] >> mp[6];

    for (int i = 1; i < 6; ++i) {
        mp[i] = std::string(n, '.');
    }
    std::string full(n, '#');
    if (mp[0] == full && full == mp[6]) {
        std::cout << "Yes\n";
        for (int i = 0; i < 7; ++i) {
            std::cout << mp[0] << "\n";
        }
        return;
    }
    if (mp[0] == full || mp[6] == full) {
        std::cout << "No\n";
        return;
    }


    for (int i = 0; i < n; ++i) {
        mp[1][i] = mp[0][i] == '#' ? '.' : '#';
    }
    for (int i = 0; i < n; ++i) {
        mp[5][i] = mp[6][i] == '#' ? '.' : '#';
    }

    int x0 = -1, x1 = -1;
    for (int i = 0; i + 1 < n; ++i) {
        if (mp[0].substr(i, 2) == "#.") {
            x0 = i;
            break;
        } else if (mp[0].substr(i, 2) == ".#") {
            x0 = i + 1;
            break;
        }
    }

    for (int i = 0; i + 1 < n; ++i) {
        if (mp[6].substr(i, 2) == "#.") {
            x1 = i;
            break;
        } else if (mp[6].substr(i, 2) == ".#") {
            x1 = i + 1;
            break;
        }
    }

    assert(x0 != -1 && x1 != -1);

    mp[2][x0] = '#';
    mp[4][x1] = '#';

    if (x0 > x1) std::swap(x0, x1);

    if (x0 == x1 || x0 + 1 == x1) {
        mp[3][x0] = '#';
    } else {
        for (int i = x0 + 1; i < x1; ++i) {
            mp[3][i] = '#';
        }
    }


    std::cout << "Yes\n";
    for (int i = 0; i < 7; ++i) {
        std::cout << mp[i] << "\n";
    }
}

int main() {
    // std::cin.tie(nullptr);
    // std::ios::sync_with_stdio(false);


    int t;
    std::cin >> t;
    while(t--){
        solve();
    }

    return 0;
}