#include <bits/stdc++.h>
using namespace std;
int main() {
  printf("YES\n");
  int n;
  string s, t;
  cin >> n >> s >> t;
  string a[3] = {"a", "b", "c"};
  for (int((i)) = (0); ((i)) < ((3)); ++((i)))
    for (int((j)) = (0); ((j)) < ((3)); ++((j)))
      for (int((k)) = (0); ((k)) < ((3)); ++((k)))
        if (i != j && j != k && k != i) {
          string ans = a[i] + a[j] + a[k] + a[i];
          bool flag = true;
          for (int((l)) = (0); ((l)) < (((3 - (n == 1)))); ++((l))) {
            if ((ans[l] == s[0] && ans[l + 1] == s[1]) ||
                (ans[l] == t[0] && ans[l + 1] == t[1])) {
              flag = false;
              break;
            }
          }
          if (flag) {
            ans = "";
            for (int((l)) = (0); ((l)) < ((n)); ++((l)))
              ans += a[i] + a[j] + a[k];
            cout << ans << "\n";
            return 0;
          }
          if ((s[0] == s[1] || t[0] == t[1]) && n > 1) continue;
          string u = a[i] + a[j];
          string v = a[j] + a[k];
          if (u != s && u != t && v != s && v != t) {
            ans = "";
            for (int((l)) = (0); ((l)) < ((n)); ++((l))) ans += a[i];
            for (int((l)) = (0); ((l)) < ((n)); ++((l))) ans += a[j];
            for (int((l)) = (0); ((l)) < ((n)); ++((l))) ans += a[k];
            cout << ans << "\n";
            return 0;
          }
        }
}
