Problem: You are given a binary string s consisting of n zeros and ones.

Your task is to divide the given string into the minimum number of subsequences in such a way that each character of the string belongs to exactly one subsequence and each subsequence looks like "010101 ..." or "101010 ..." (i.e. the subsequence should not contain two adjacent zeros or ones).

Recall that a subsequence is a sequence that can be derived from the given sequence by deleting zero or more elements without changing the order of the remaining elements. For example, subsequences of "1011101" are "0", "1", "11111", "0111", "101", "1001", but not "000", "101010" and "11100".

You have to answer t independent test cases.

Input

The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.

The first line of the test case contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the length of s. The second line of the test case contains n characters '0' and '1' — the string s.

It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).

Output

For each test case, print the answer: in the first line print one integer k (1 ≤ k ≤ n) — the minimum number of subsequences you can divide the string s to. In the second line print n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ k), where a_i is the number of subsequence the i-th character of s belongs to.

If there are several answers, you can print any.

Example

Input


4
4
0011
6
111111
5
10101
8
01010000


Output


2
1 2 2 1 
6
1 2 3 4 5 6 
1
1 1 1 1 1 
4
1 1 1 1 1 2 3 4 

Solution (in JAVA):

Solution:
/*
If you want to aim high, aim high
Don't let that studying and grades consume you
Just live life young
******************************
What do you think? What do you think?
1st on Billboard, what do you think of it
Next is a Grammy, what do you think of it
However you think, I’m sorry, but shit, I have no fcking interest
*******************************
I'm standing on top of my Monopoly board
That means I'm on top of my game and it don't stop
til my hip don't hop anymore
https://www.a2oj.com/Ladder16.html
*******************************
300iq as writer = Sad!
*/
import java.util.*;
import java.io.*;
import java.math.*;

   public class D
   {
      public static void main(String hi[]) throws Exception
      {
         BufferedReader infile = new BufferedReader(new InputStreamReader(System.in));
         StringTokenizer st = new StringTokenizer(infile.readLine());
         int T = Integer.parseInt(st.nextToken());
         StringBuilder sb = new StringBuilder();
         while(T-->0)
         {
            int N = Integer.parseInt(infile.readLine());
            char[] arr = infile.readLine().toCharArray();
            TreeSet<Integer>[] sets = new TreeSet[2];
            sets[0] = new TreeSet<Integer>();
            sets[1] = new TreeSet<Integer>();
            int[] res = new int[N];
            for(int i=0; i < N; i++)
               sets[arr[i]-'0'].add(i);
            int curr = 1;
            while(sets[0].size() > 0)
            {
               int dex = sets[0].first();
               int tag = 0;
               if(sets[1].size() > 0 && dex > sets[1].first())
               {
                  dex = sets[1].first();
                  tag = 1;
               }
               sets[tag].remove(dex);
               res[dex] = curr;
               while(true)
               {
                  if(sets[tag^1].size() == 0 || sets[tag^1].last() < dex)
                     break;
                  dex = sets[tag^1].ceiling(dex);
                  sets[tag^1].remove(dex);
                  tag ^= 1;
                  res[dex] = curr;
               }
               curr++;
            }
            for(int dex: sets[1])
               res[dex] = curr++;
            sb.append(curr-1).append("\n");
            for(int x: res)
               sb.append(x+" ");
            sb.append("\n");
         }
         System.out.print(sb);
      }
   }