#include <bits/stdc++.h>
#define int long long
using namespace std;
const int NMAX=(1 << 17);
int n;
vector <int> a, poz;
vector <int> xored (int x)
{
vector <int> ret;
for (int bit=0;bit<n;bit++)
{
ret.push_back (1);
if (x & (1 << bit))
ret.push_back (0);
}
return ret;
}
void fct (vector <int> &v, int type)
{
if (type==0)
{
for (int i=0;i<(1 << n);i++)
v[i]^=(1 << (n-1));
}
else
{
for (int i=0;i<v.size();i++)
{
if (v[i]%2)
v[i]=v[i]/2+(1 << (n-1));
else
v[i]/=2;
}
}
}
int32_t main ()
{
ios_base :: sync_with_stdio (0);
cin.tie (nullptr);
cin >> n;
a.resize (1 << n);
poz.resize (1 << n);
for (int i=0;i<(1 << n);i++)
cin >> a[i], poz[a[i]]=i;
int ans=1e18;
vector <int> op;
fct (poz, 1);
for (int i=0;i<n;i++)
{
vector <vector <int>> before (n, vector <int> ((1 << n), 0));
vector <vector <int>> p (n, vector <int> (2, 0));
for (int j=0;j<(1 << n);j++)
{
int val=0;
for (int bit=n-1;bit>=0;bit--)
{
if (poz[j]& (1 << bit))
{
p[bit][1]+=before[bit][val];
val+=(1 << bit);
}
else
{
p[bit][0]+=before[bit][val+(1 << bit)];
}
before[bit][val]++;
}
}
int sum=0, x=0;
for (int j=0;j<n;j++)
{
if (p[j][1]<p[j][0])
x^=(1 << j);
sum+=min (p[j][1], p[j][0]);
}
if (sum<ans)
{
ans=sum;
vector <int> crt=xored (x);
op.clear ();
for (int j=0;j<=i;j++)
op.push_back (1);
for (auto chestie : crt)
op.push_back (chestie);
}
fct (poz, 1);
}
if (n==0)
ans=0;
cout << ans << "\n";
for (auto chestie : op)
cout << (chestie==0?1:2);
return 0;
}
