#include<cstdio>
#include<vector>
#include<cstring>
#include<cmath>
#include<cstdlib>
#include<ctime>
#include<map>
#include<set>
#include<queue>
#include<algorithm>

using namespace std;


int main()
{
//freopen ("output", "w", stdout);

printf ("20\n");
for (int i=1; i<=20; i++)
    printf ("%d ", (1<<i));
printf ("\n");

return 0;
}