#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  string s1, s2;
  cin >> n >> s1 >> s2;
  cout << "YES" << endl;
  if (s1[0] == s1[1] && s2[0] == s2[1]) {
    for (int i = 0; i < n; i++) {
      cout << "abc";
    }
    cout << endl;
    return 0;
  }
  if (s1[0] == s1[1] || s2[0] == s2[1]) {
    if (s2[0] == s2[1]) {
      string ans = s2;
      s2 = s1;
      s1 = ans;
    }
    if (s2[1] == s1[0]) {
      int ss = 'a' + 'b' + 'c';
      ss -= s1[0];
      ss -= s2[0];
      for (int i = 1; i <= n; i++) {
        cout << s1[0] << char(ss);
      }
      for (int i = 1; i <= n; i++) {
        cout << s2[0];
      }
      cout << endl;
    } else {
      int ss = 'a' + 'b' + 'c';
      ss -= s1[0];
      ss -= s2[1];
      for (int i = 1; i <= n; i++) {
        cout << s2[1];
      }
      for (int i = 1; i <= n; i++) {
        cout << (char)ss << s1[0];
      }
      cout << endl;
    }
    return 0;
  }
  string s[10];
  s[1] = "abc";
  s[2] = "acb";
  s[3] = "bac";
  s[4] = "bca";
  s[5] = "cab";
  s[6] = "cba";
  for (int i = 1; i <= 6; i++) {
    if ((s[i][0] == s1[0] && s[i][1] == s1[1]) ||
        (s[i][0] == s2[0] && s[i][1] == s2[1]) ||
        (s[i][1] == s1[0] && s[i][2] == s1[1]) ||
        (s[i][1] == s2[0] && s[i][2] == s2[1])) {
      continue;
    } else {
      for (int j = 0; j < 3; j++) {
        for (int k = 0; k < n; k++) {
          cout << s[i][j];
        }
      }
      cout << endl;
      break;
    }
  }
}
