#include <bits/stdc++.h>
using namespace std;
const int MAXN = 5e5 + 50;
inline long long int max(long long int a, long long int b) {
  return ((a > b) ? a : b);
}
inline long long int min(long long int a, long long int b) {
  return ((a > b) ? b : a);
}
inline long long int gcd(long long int a, long long int b) {
  if (b == 0) return a;
  a %= b;
  return gcd(b, a);
}
long long int n, i;
void sol() {
  cin >> n;
  string s, t;
  cin >> s >> t;
  string abc = "abc";
  vector<string> res;
  do {
    string cur;
    for (i = 0; i < n; i++) cur += abc;
    res.push_back(cur);
    res.push_back(string(n, abc[0]) + string(n, abc[1]) + string(n, abc[2]));
  } while (next_permutation(abc.begin(), abc.end()));
  for (auto str : res) {
    if (str.find(s) == string::npos && str.find(t) == string::npos) {
      cout << "YES" << endl << str << endl;
      return;
    }
  }
  return;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  sol();
}
