#include<iostream>
#include<cstdio>
#define N 22
using namespace std;
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
int n,cl[1<<N],a[1<<N],length,nt[1<<N],leng,st[N+1];
bool used[1<<N];
void solve(int x,int d)
{
	if (d==n)
	{
		a[x]=++length;
		return;
	}
	solve(x<<1,d+1);
	int ps=length;
	for (int i=2;i<=ps;++i)
		if (i!=a[x<<1])
			nt[i]=++length;
	nt[a[x<<1]]=a[x<<1],a[x]=++length;
	for (int i=d+1;i<=n;++i)
		for (int j=(x<<(i-d));j<(x<<(i-d))+(1<<(i-d-1));++j)
			a[(x<<(i-d+1))+(1<<(i-d))-1-j]=nt[a[j]];
	if (d) a[(x<<(n-d))|((1<<(n-d))-1)]=a[x];
	else a[(x<<(n-d))|((1<<(n-d))-1)]=++length;
	if (n-d>=3&&d)
	{
		int ds=x;
		leng=0;
		while (ds<=(1<<(n+1))-1) st[++leng]=a[ds],ds=(ds<<1)|1;
		for (int i=1;i<=leng-i+1;++i)
			if (st[i]!=st[leng-i+1])
			{
				for (int j=1;j<=(1<<(n+1))-1;++j)
					if (a[j]==st[leng-i+1])
						a[j]=st[i];
			}
	}
	return;
}
int main()
{
	n=read();
	if (n==1)
	{
		puts("1");
		puts("1 1 1");
		return 0;
	}
	solve(1,0);
	for (int i=1;i<=(1<<(n+1))-1;++i) used[a[i]]=1;
	leng=0;
	for (int i=1;i<=length;++i)
		if (used[i])
			cl[i]=++leng;
    printf("%d\n",leng);
	for (int i=1;i<=(1<<(n+1))-1;++i) printf("%d ",cl[a[i]]);
	puts("");
	return 0;
}