#include <bits/stdc++.h>
using namespace std;
int main(int argc, char const *argv[]) {
  int n;
  cin >> n;
  string a1, a2, tmp = "abc";
  cin >> a1 >> a2;
  bool check = false;
  bool check2 = false;
  do {
    string tmp2 = "", tmp3 = "";
    if (n > 1)
      tmp2 = tmp + tmp;
    else
      tmp2 = tmp;
    if (tmp2.find(a1) == -1 && tmp2.find(a2) == -1) {
      check = true;
      break;
    }
    for (int i = 0; i < 3; i++) {
      for (int j = 0; j < 3; j++) tmp3 += tmp[i];
    }
    if (tmp3.find(a1) == -1 && tmp3.find(a2) == -1) {
      check2 = true;
      break;
    }
  } while (next_permutation(tmp.begin(), tmp.end()));
  if (check) {
    cout << "YES" << endl;
    for (int i = 0; i < n; i++) cout << tmp;
  } else if (check2) {
    cout << "YES" << endl;
    for (int i = 0; i < n; i++) cout << tmp[0];
    for (int i = 0; i < n; i++) cout << tmp[1];
    for (int i = 0; i < n; i++) cout << tmp[2];
  } else
    cout << "NO" << endl;
}
