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#include <bits/stdc++.h>

using namespace std;

long long bits1toN(long long n) {
  long long acc = 0;
  while (n) {
    int lg = __lg(n);
    int pow = 1 << lg;
    n = n ^ pow;
    acc += lg * pow / 2 + n + 1;
  }
  return acc;
}

constexpr int step = 256;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int n;
  cin >> n;

  // Binary search is faster, but not required as n is less than 10^6
  int top = step;
  int val;
  vector<int> incl;
  while ((val = bits1toN(top)) < n) {
    top += step;
  }

  while (val != n) {
    int bits = __builtin_popcount(top);
    if (__builtin_expect(val - bits < n, 0)) {
      incl.push_back(top);
    } else {
      val -= bits;
    }
    top--;
  }
  cout << incl.size() + top << '\n';
  for (auto i : incl) {
    cout << i << ' ';
  }
  for (int i = top; i > 1; i--) {
    cout << i << ' ';
  }
  cout << "1\n";
}