#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  scanf("%d", &n);
  string s, t;
  cin >> s >> t;
  for (char i5 = 'a'; i5 <= 'c'; i5++)
    for (char i6 = 'a'; i6 <= 'c'; i6++)
      for (char i7 = 'a'; i7 <= 'c'; i7++) {
        if (i5 == i6 || i5 == i7 || i6 == i7) continue;
        string ans;
        ans += i5;
        ans += i6;
        ans += i7;
        string ans2;
        ans2 += ans;
        ans2 += ans;
        if (ans2.find(s) != -1 || ans2.find(t) != -1) continue;
        puts("YES");
        for (int i = 1; i <= n; i++) cout << ans;
        return 0;
      }
  vector<char> v;
  v.push_back('a');
  v.push_back('b');
  v.push_back('c');
  do {
    string ss;
    ss += v[0];
    ss += v[1];
    string tt;
    tt += v[1];
    tt += v[2];
    if (ss == s || ss == t) continue;
    if (tt == s || tt == t) continue;
    puts("YES");
    for (int i = 1; i <= n; i++) cout << v[0];
    for (int i = 1; i <= n; i++) cout << v[1];
    for (int i = 1; i <= n; i++) cout << v[2];
    return 0;
  } while (next_permutation(v.begin(), v.end()));
  return 0;
}
