#include <iostream>
#include <fstream>
#include <algorithm>
#include <math.h>
#include <string>
#include <vector>
#include <stdio.h>
#include <queue>

#define LL long long
#define pb push_back
#define lm 10001
#define MOD 1000000007

using namespace std;

int main()
{
    //freopen("data.in","r",stdin);

    cout<<20<<'\n';
    for (int i=0; i<20; i++)
    {
        cout<<(1<<i)<<' ';
    }

    return 0;
}