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 PYTHON3):

Solution:
#_______________________________________________________________#
def fact(x):
	if x == 0:
		return 1
	else:
		return x * fact(x-1)
def lower_bound(li, num): #return 0 if all are greater or equal to
	answer = len(li)-1
	start = 0
	end = len(li)-1

	while(start <= end):
		middle = (end+start)//2
		if li[middle] >= num:
			answer = middle
			end = middle - 1
		else:
			start = middle + 1
	return answer #index where x is not less than num
def upper_bound(li, num): #return n-1 if all are small or equal
	answer = -1
	start = 0
	end = len(li)-1

	while(start <= end):
		middle = (end+start)//2

		if li[middle] <= num:
			answer = middle
			start = middle + 1
		
		else:
			end = middle - 1
	return answer #index where x is not greater than num

def abs(x):
	return x if x >=0 else -x
def binary_search(li, val, lb, ub): # ITS A BINARY
	ans = 0
	while(lb <= ub):
		mid = (lb+ub)//2
		#print(mid, li[mid])
		if li[mid] > val:
			ub = mid-1
		elif val > li[mid]:
			lb = mid + 1
		else:
			ans = 1
			break
	return ans

def sieve_of_eratosthenes(n):
	ans = []
	arr = [1]*(n+1)
	arr[0],arr[1], i = 0, 0, 2
	while(i*i <= n):
		if arr[i] == 1:
			j = i+i
			while(j <= n):
				arr[j] = 0
				j += i
		i += 1
	for k in range(n):
		if arr[k] == 1:
			ans.append(k)
	return ans
def nc2(x):
	if x == 1:
		return 0
	else:
		return x*(x-1)//2
def kadane(x): #maximum subarray sum
	sum_so_far = 0
	current_sum = 0
	for i in x:
		current_sum += i
		if current_sum < 0:
			current_sum = 0
		else:
			sum_so_far = max(sum_so_far,current_sum)
	return sum_so_far
def mex(li):
	check = [0]*1001
	for i in li:
		check[i] += 1
	for i in range(len(check)):
		if check[i] == 0:
		 return i 
def sumdigits(n):
	ans = 0
	while(n!=0):
		ans += n%10
		n //= 10
	return ans

def product(li):
	ans = 1
	for i in li:
		ans *= i
	return ans
def maxpower(n,k):
	cnt = 0
	while(n>1):
		cnt += 1
		n //= k
	return cnt
def knapsack(li,sumi,s,n,dp):
	if s == sumi//2:
		return 1
	elif n==0:
		return 0
	else:
		if dp[n][s] != -1:
			return dp[n][s]
		else:
			if li[n-1] <= s:
				dp[n][s] = knapsack(li,sumi,s-li[n-1],n-1,dp) or knapsack(li,sumi,s,n-1,dp)
			else:
				dp[n][s] = knapsack(li,sumi,s,n-1,dp)
			return dp[n][s]
def pref(li):
	pref_sum = [0]
	for i in li:
		pref_sum.append(pref_sum[-1] + i)
	return pref_sum

#_______________________________________________________________#
'''
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'''
from math import *
from collections import deque
max_steps = 100005
for _ in range(int(input())):
#for _ in range(1):
	n = int(input())
	#n,k,z = map(int,input().split())
	s = input()
	#s2 = input()
	#n,k = map(int,input().split())
	#a = list(map(int,input().split()))
	#b = list(map(int,input().split()))
	#s = list(st)
	#a = [int(x) for x in list(s1)]
	#b = [int(x) for x in list(s2)]

	checker = [[],[]] #0 subseq and 1 subseq
	seq_num = 0
	ans = []
	for j in s:
		i = int(j)
		if len(checker[i]):
			transfer = checker[i].pop()
			checker[1-i].append(transfer)
			ans.append(checker[1-i][-1]) #transfered element
		else:
			seq_num += 1
			checker[1-i].append(seq_num)
			ans.append(seq_num)
	print(seq_num)
	print(*ans)