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#include <iostream>
using namespace std;

int main() {
	int n;
	cin >> n;
	int popcount = 0;
	int next = 1;
	while (popcount < n) {
		popcount += __builtin_popcount(next);
		next += 1;
	}
	int ban = -1;
	if (popcount > n) {
		for (int i = next - 1; i > 0; --i) {
			if (ban == -1 && __builtin_popcount(i) == popcount - n) {
				ban = i;
			}
		}
	}
	cout << (next - 1 - (popcount != n)) << "\n";
	for (int i=next - 1; i > 0; --i) {
		if (ban == i) continue;
		cout << i << ' ';
	}
}