// #include <bits/stdc++.h>
#include <iostream>
#include <cmath>
#include <algorithm>
#include <map>
#include <unordered_map>
#include <vector>
#include <iomanip>
#include <string>
#include <queue>
#include <set>
#include <deque>
using namespace std;
#define int long long
#define endl "\n"
#define fi first
#define se second
const int M=1e9+7;
const int inf = 1e14;
const int LOG=17;
const int N=2e5+5;
int n , m , c , w , k , t=1 , q=1 , x , y , z , l , r;
int fn[N];
void up(int i,int x){
if (i<N){
fn[i]+=x;
up(i+(i&-i),x);
}
}
int pr(int i){
if (i==0)return 0;
return fn[i]+pr(i-(i&-i));
}
void solve(){
cin >> n;
vector<int>a(1<<n);
for (int i=0;i<(1<<n);i++){
cin >> x;
a[x]=i;
}
if (n==0){
cout << 0 << endl;
cout << 1 << endl;
return;
}
vector<int>b=a;
int mn=inf;
int in=0,xo=0;
for (int k=0;k<n;k++){
int uo=0;
for (int j=n-1;j>=0;j--){
uo^=(1<<j);
int c1=0,c2=0;
for (int i=0;i<=(1<<n);i++){
fn[i]=0;
}
for (int i=0;i<(1<<n);i++){
c1+=i-pr(a[i]);
up(a[i]+1,1);
}
vector<int>vi(1<<n);
for (int i=0;i<(1<<n);i++){
a[i]^=(1<<j);
}
for (int i=0;i<=(1<<n);i++){
fn[i]=0;
}
for (int i=0;i<(1<<n);i++){
c2+=i-pr(a[i]);
up(a[i]+1,1);
}
if (c1<=c2){
uo^=(1<<j);
vector<int>vi(1<<n);
for (int i=0;i<(1<<n);i++){
a[i]^=(1<<j);
}
}
int u=min(c1,c2);
if (u<mn){
mn=u;
in=k;
xo=uo;
}
}
a=b;
for (int i=0;i<(1<<n);i++){
int u=(a[i]&(1<<(n-1)));
a[i]-=u;
a[i]*=2;
a[i]+=(u==(1<<(n-1)));
}
b=a;
}
string s;
for (int i=0;i<in;i++){
s+='2';
}
for (int i=n-1;i>=0;i--){
if (xo&(1<<i)){
s+='1';
}
s+='2';
}
// for (int j=0;j<in;j++){
// for (int i=0;i<(1<<n);i++){
// int u=(a[i]&(1<<(n-1)));
// a[i]-=u;
// a[i]*=2;
// a[i]+=(u==(1<<(n-1)));
// }
// }
// int c=0;
// for (int i=0;i<=(1<<n);i++){
// fn[i]=0;
// }
// for (int i=0;i<(1<<n);i++){
// c+=i-pr(a[i]);
// up(a[i]+1,1);
// }
cout << mn << endl;
// for (int i:a){
// cout << i << " ";
// }
// cout << endl;
cout << s << endl;
}
signed main()
{
ios::sync_with_stdio(0);//DO NOT USE IN INTERACTIVE
cin.tie(0), cout.tie(0);//DO NOT USE IN INTERACTIVE
cout << fixed << setprecision(9);
srand(time(0));
// int t=1;
// cin >> t;
for (int _=1;_<=t;_++){
solve();
q++;
}
}
