#include <bits/stdc++.h>
#pragma warning(disable : 4996)
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("-ffloat-store")
using namespace std;
clock_t time_p = clock();
void aryanc403() {
  time_p = clock() - time_p;
  cerr << "Time Taken : " << (float)(time_p) / CLOCKS_PER_SEC << "\n";
}
const long long int INF = 0xFFFFFFFFFFFFFFFL;
long long int seed;
mt19937 rng(seed = chrono::steady_clock::now().time_since_epoch().count());
inline long long int rnd(long long int l = 0, long long int r = INF) {
  return uniform_int_distribution<long long int>(l, r)(rng);
}
class CMP {
 public:
  bool operator()(pair<long long int, long long int> a,
                  pair<long long int, long long int> b) {
    return !(a.first < b.first || a.first == b.first && a.second == b.second);
  }
};
void add(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt == m.end())
    m.insert({x, cnt});
  else
    jt->second += cnt;
}
void del(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt->second <= cnt)
    m.erase(jt);
  else
    jt->second -= cnt;
}
bool cmp(const pair<long long int, long long int> &a,
         const pair<long long int, long long int> &b) {
  return a.first < b.first || (a.first == b.first && a.second < b.second);
}
const long long int mod = 1000000007L;
long long int T, n, i, j, k, in, cnt, l, r, u, v, x, y;
long long int m;
string s, a, b;
char perm[256];
char used[256];
bool solve(long long int i, bool fl) {
  long long int j;
  if (i == n) {
    for (j = 0; j < (n); ++j) {
      if (b[j] < perm[s[j]])
        return false;
      else if (b[j] > perm[s[j]])
        break;
    }
    return true;
  }
  if (perm[s[i]] != -1) {
    if (!fl && a[i] > perm[s[i]]) return false;
    fl |= (a[i] < perm[s[i]]);
    return solve(i + 1, fl);
  }
  if (fl) {
    for (j = 'a'; j < 'a' + k; ++j) {
      if (used[j] != -1) continue;
      perm[s[i]] = j;
      used[j] = s[i];
      if (solve(i + 1, fl)) return true;
      perm[s[i]] = used[j] = -1;
      return false;
    }
    assert(false);
  }
  if (used[a[i]] == -1) {
    perm[s[i]] = a[i];
    used[a[i]] = s[i];
    if (solve(i + 1, fl)) return true;
    perm[s[i]] = used[a[i]] = -1;
  }
  for (char j = a[i] + 1; j < 'a' + k; ++j) {
    if (used[j] != -1) continue;
    perm[s[i]] = j;
    used[j] = s[i];
    if (solve(i + 1, true)) return true;
    used[j] = perm[s[i]] = -1;
  }
  return false;
}
int main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> T;
  while (T--) {
    cin >> k;
    cin >> s;
    cin >> a;
    cin >> b;
    n = (long long int)s.size();
    memset(perm, -1, 256 * sizeof(char));
    memset(used, -1, 256 * sizeof(char));
    if (solve(0, false)) {
      cout << "YES"
           << "\n";
      for (long long int j = 'a'; j < k + 'a'; ++j) {
        if (used[j] != -1) continue;
        for (long long int i = 'a'; i < k + 'a'; ++i) {
          if (perm[i] != -1) continue;
          used[j] = i;
          perm[i] = j;
          break;
        }
      }
      for (j = 0; j < (k); ++j) cout << perm[j + 'a'];
      cout << "\n";
    } else
      cout << "NO"
           << "\n";
  }
  aryanc403();
  return 0;
}
