#include <bits/stdc++.h>
using namespace std;
int II() {
  int q;
  scanf("%d", &q);
  return q;
}
long long LII() {
  long long q;
  scanf("%lld", &q);
  return q;
}
string s, t;
int N;
void solve() {
  cin >> N >> s >> t;
  string ss = "abc";
  vector<string> v;
  do {
    string res = string(N, ss[0]) + string(N, ss[1]) + string(N, ss[2]);
    v.push_back(res);
    res = "";
    for (int i = 1; i <= N; i++) res += ss;
    v.push_back(res);
  } while (next_permutation(ss.begin(), ss.end()));
  for (auto it : v) {
    if (it.find(s) == string::npos && it.find(t) == string::npos) {
      cout << "YES" << endl;
      cout << it << endl;
      return;
    }
  }
}
int32_t main() {
  int tt;
  tt = 1;
  int cas = 1;
  while (tt--) {
    solve();
  }
}
