#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> PII;
void solve() {
   int n;
   cin >> n;
   string a, b;
   cin >> a >> b;
   int t = count(a.begin(), a.end(), '#');
   int t1 = count(b.begin(), b.end(), '#');
   // cerr << t << " " << t1 << endl;
   if (t == n) {
      if (t1 == n) {
         cout << "Yes\n";
         for (int i = 0; i < 7; i++) {
            cout << a << endl;
         }
      } else {
         cout << "No\n";
      }
      return;
   } else {
      if (t1 == n) {
         cout << "No\n";
        return;
      }
   }
   cout << "Yes\n";
   string s2, s6;
   for (int i = 0; i < n; i++) {
      if (a[i] == '#') s2 += '.';
      else {
         s2 += '#';
      }
   }
   string s3 = string(n, '.');
   int f1 = 0, f2 = 0;
   for (int i = 1; i < n; i++) {
      if (s2[i] != s2[i - 1]) {
         if (s2[i] == '#') {
            s3[i - 1] = '#';
            f1 = i - 1;
         } else {
            s3[i] = '#';
            f1 = i;
         }
         break;
      }
   }
   for (int i = 0; i < n; i++) {
      if (b[i] == '#') s6 += '.';
      else {
         s6 += '#';
      }
   }
   string s5 = string(n, '.');
   for (int i = 1; i < n; i++) {
      if (s6[i] != s6[i - 1]) {
         if (s6[i] == '#') {
            s5[i - 1] = '#';
            f2 = i - 1;
         } else {
            s5[i] = '#';
            f2 = i;
         }
         break;
      }
   }
   string s4 = string(n, '.');
   if (f1 == f2) {
      s4[f1] = '#';
   } else if (abs(f1 - f2) == 1) {
      s4[f1] = '#';
   } else {
      if (f1 > f2) swap(f1, f2);
      for (int i = f1 + 1; i < f2; i++) {
         s4[i] = '#';
      }
   }
   cout << a << endl;
   cout << s2 << endl;
   cout << s3 << endl;
   cout << s4 << endl;
   cout << s5 << endl;
   cout << s6 << endl;
   cout << b << endl;
}
signed main() {
   ios::sync_with_stdio(false);
   cin.tie(0);
   cout.tie(0);
   int t;
   cin >> t;
   while (t--) {
      solve();
   }
}