func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1000000;   int aa[N + 1];   int main() {     int n;     cin >> n;     long long ans = 0;     for (int i = 0; i <= n; i++) aa[i] = i;     int n_ = n;     for (int h = 20; n_ > 0;) {       while (h >= 0 && (n_ & 1 << h) == 0) h--;       int m = n_ - ((1 << h) - 1);       reverse(aa + n_ - m * 2 + 1, aa + n_ + 1);       n_ -= m * 2;       ans += m * 2LL * ((1 << h + 1) - 1);     }     cout << ans <<   n ;     for (int i = 0; i <= n; i++) cout << aa[i] <<    ;     cout <<   n ;     return 0;   }   