func_code_string: #include <bits/stdc++.h>   using namespace std;   const double EPS = 1e-8;   const int INFI = 1000 * 1000 * 1000;   const long long INFL = 1000LL * 1000LL * 1000LL * 1000LL * 1000LL;   const int MX_N = 1000;   int N;   string s, t;   string strs[] = { abc ,  acb ,  bac ,  bca ,  cab ,  cba };   int nstrs = 6;   int main() {     cin >> N;     cin >> s >> t;     int dobc = 0;     cout <<  YES  << endl;     if (s[0] == s[1]) ++dobc;     if (t[0] == t[1]) ++dobc;     if (N == 1 || !dobc) {       for (int i = 0; i < nstrs; ++i) {         string s1 = strs[i].substr(0, 2);         string s2 = strs[i].substr(1, 2);         if (s == s1 || s == s2 || t == s1 || t == s2) continue;         for (int j = 0; j < 3; ++j)           for (int k = 0; k < N; ++k) cout << strs[i][j];         putchar(  n );         return 0;       }     } else {       for (int i = 0; i < nstrs; ++i) {         bool pass = true;         string ap = strs[i] + strs[i];         for (int j = 0; j < ap.size() - 1 && pass; ++j) {           string sb = ap.substr(j, 2);           if (s == sb || t == sb) pass = false;         }         if (!pass) continue;         for (int j = 0; j < N; ++j) cout << strs[i];         cout << endl;         break;       }     }     return 0;   }   