func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename A, typename B>   inline void chmin(A &a, B b) {     if (a > b) a = b;   }   template <typename A, typename B>   inline void chmax(A &a, B b) {     if (a < b) a = b;   }   string S;   long long dp[3333333];   signed main() {     for (long long i = 0; i < 26; i++) S += (char)( a  + i);     for (long long i = 0; i < 26; i++) S += (char)( A  + i);     fill_n(dp, 1111111, INT_MAX);     dp[1] = 0;     for (long long i = 1; i < 1111111; i++) {       for (long long j = 1; j <= 2; j++) {         chmin(dp[i * j + 1], dp[i] + 1);       }     }     long long n;     cin >> n;     string s;     long long cur = 0;     while (n > 1) {       if ((n - 1) & 1) {         s += string(1, S[cur++]);         n--;       } else {         s += string(2, S[cur++]);         n = (n - 1) / 2;       }     }     for (long long i = 0; i < S.size(); i++) s += S[i];     cout << s <<     << S << endl;     return 0;   }   