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#include <iostream>
#include <unordered_set>

using namespace std;

int count_bits(int n) {
  int bits = 0;
  while (n > 0) {
    if (n % 2 == 1) {
      bits++; 
    }
    n >>= 1;
  }
  return bits;
}

int main() {
  int n;
  cin >> n;

  int i = 1;
  int bits = 0;
  while (bits < n)  {
    bits += count_bits(i++);
  }
  i--;


  unordered_set<int> ignore;
  for (int j = i; j > 0 && bits > n; j--) {
    int j_bits = count_bits(j);
    if (bits - j_bits >= n) {
      bits -= j_bits;
      ignore.insert(j);
    }
  }

  cout << (i - ignore.size()) << endl;

  for (int j = i; j > 0; j--) {
    if (ignore.count(j) == 0) {
      cout << j << " ";
    }
  }

  cout << endl;

  return 0;
}