#include <bits/stdc++.h>
using namespace std;
int64_t MOD = 1000000007;
int32_t main() {
  ios_base ::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int64_t n;
  cin >> n;
  string s, t;
  cin >> s >> t;
  vector<string> v;
  string curr = "abc";
  do {
    string s1 = "";
    for (int64_t i = 0; i < n; i++) s1 += curr;
    v.push_back(s1);
    v.push_back(string(n, curr[0]) + string(n, curr[1]) + string(n, curr[2]));
  } while (next_permutation(curr.begin(), curr.end()));
  for (auto str : v) {
    if (str.find(s) == string::npos && str.find(t) == string::npos) {
      cout << "YES" << '\n' << str << '\n';
      return 0;
    }
  }
  cout << "NO" << '\n';
  return 0;
}
