#include <bits/stdc++.h>

int count(std::string &s, char c) {
  int cnt = 0;
  for (char x : s) {
    if (x == c) {
      ++cnt;
    }
  }
  return cnt;
}

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

  // if (a == b) {
  //   std::cout << "Yes\n";
  //   for (int i = 0; i < 7; ++i) {
  //     std::cout << a << '\n';
  //   }
  //   return;
  // }

  int cnt1 = count(a, '#');
  int cnt2 = count(b, '#');

  if ((cnt1 == n and cnt2 < n) or (cnt1 < n and cnt2 == n)) {
    std::cout << "No\n";
    return;
  }

  std::cout << "Yes\n";
  if (cnt1 == n and cnt2 == n) {
    for (int i = 1; i <= 7; ++i) {
      std::cout << std::string(n, '#') << '\n';
    }
    return;
  }

  auto ans = std::vector(7, std::string(n, '.'));
  ans[0] = a, ans[6] = b;

  int pos1 = -1, pos2 = -1;
  {
    auto &x = ans[1], &y = ans[5];
    for (int i = 0; i < n; ++i) {
      x[i] = a[i] == '#' ? '.' : '#';
      y[i] = b[i] == '#' ? '.' : '#';
    }

    auto check = [&](std::string &s, int p) {
      int n = s.size();
      if (p == 0)
        return s[0] == '.' and s[1] == '#';
      if (p == n - 1)
        return s[p] == '.' and s[p - 1] == '#';
      return s[p] == '.' and (s[p - 1] == '#' or s[p + 1] == '#');
    };

    for (int i = 0; i < n; ++i) {
      if (pos1 == -1 and check(x, i)) {
        pos1 = i;
      }

      if (pos2 == -1 and check(y, i)) {
        pos2 = i;
      }
    }
  }

  {
    auto &x = ans[2], &y = ans[4];
    x[pos1] = y[pos2] = '#';

    auto &z = ans[3];
    if (std::abs(pos1 - pos2) > 1) {
      for (int i = std::min(pos1, pos2) + 1; i < std::max(pos1, pos2); ++i) {
        z[i] = '#';
      }
    } else {
      z[pos1] = '#';
    }
  }

  for (auto &s : ans) {
    std::cout << s << '\n';
  }
}

int main() {
  std::cin.tie(nullptr)->sync_with_stdio(false);

  int T;
  std::cin >> T;

  while (T--) {
    solve();
  }
}