#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int n;
  cin >> n;
  string s, t, p = "abc";
  cin >> s >> t;
  vector<string> v;
  do {
    string cur = "";
    for (int i = 0; i < n; i++) {
      cur += p;
    }
    v.push_back(cur);
    v.push_back(string(n, p[0]) + string(n, p[1]) + string(n, p[2]));
  } while (next_permutation(p.begin(), p.end()));
  for (int i = 0; i < v.size(); i++) {
    if (v[i].find(s) == string::npos && v[i].find(t) == string::npos) {
      cout << "YES\n" << v[i] << "\n";
      break;
    }
  }
  return 0;
}
