#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long 
#define db double
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define FR first
#define SE second
#define int long long
using namespace std;
inline int read() {
  int x = 0; bool op = false;
  char c = getchar();
  while(!isdigit(c))op |= (x == '-'), c = getchar();
  while(isdigit(c))x = (x << 1) + (x << 3) + (c ^ 48), c = getchar();
  return op ? -x : x;
}
const int N = (1 << 17) + 10;
const int INF = 1e16;
int n;
int p[N], cnt[N][2];
signed main() {
  n = read();
  for(int i = 0; i < (1 << n); i++)p[read()] = i;
  int ans = INF, pos = 0, S = 0;
  for(int i = 0; i <= n; i++) {
    int val = 0, res = 0;
  // for(int k = 0; k < (1 << n); k++)printf("%d ", p[k]); putchar('\n');
    for(int j = n - 1; ~j; j--) {
      int sum[2] = {0};
      for(int k = 0; k < (1 << n); k++) {
        int c = p[k] >> j & 1;
        sum[c] += cnt[p[k] >> (j + 1)][c ^ 1];
        cnt[p[k] >> (j + 1)][c]++;
        // printf("sum:%d %d\n", sum[0], sum[1]);
      }
      // printf("qwq:%d %d %d\n", j, sum[0], sum[1]);
      for(int k = 0; k < (1 << n); k++) {
        int c = p[k] >> j & 1;
        cnt[p[k] >> (j + 1)][c]--;
      }
      int now = sum[1] < sum[0];
      if(now)val |= (1 << j);
      res += min(sum[0], sum[1]);
    }
    // printf("stra:%d\n", val);
    if(res < ans)ans = res, pos = i, S = val;
    for(int j = 0; j < (1 << n); j++) {
      p[j] = (p[j] >> 1) | ((p[j] & 1) * (1 << (n - 1)));
    }
  }
  printf("%lld\n", ans);
  // printf("S:%d %d\n", pos, S);
  string opt = "";
  for(int i = 0; i <= pos; i++)opt += "2";
  for(int i = 0; i < n; i++) {
    if(S >> i & 1)opt += "1";
    if(i + 1 < n)opt += "2";
  }
  cout << opt << '\n';
  return 0;
}