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:
# Author Name: Ajay Meena
# Codeforce : https://codeforces.com/profile/majay1638
import sys
import math
import bisect
import heapq
from bisect import bisect_right
from sys import stdin, stdout

# -------------- INPUT FUNCTIONS ------------------


def get_ints_in_variables(): return map(
    int, sys.stdin.readline().strip().split())


def get_int(): return int(sys.stdin.readline())


def get_ints_in_list(): return list(
    map(int, sys.stdin.readline().strip().split()))
def get_list_of_list(n): return [list(
    map(int, sys.stdin.readline().strip().split())) for _ in range(n)]


def get_string(): return sys.stdin.readline().strip()

# -------- SOME CUSTOMIZED FUNCTIONS-----------


def myceil(x, y): return (x + y - 1) // y

# -------------- SOLUTION FUNCTION ------------------


def Solution(s, n):
    # Write Your Code Here
    # s=[c for c in s]
    ans = []
    z = []
    o = []
    for i in range(n):
        newPos = len(z)+len(o)+1
        if s[i] == "0":
            if len(o) == 0:
                z.append(newPos)
            else:
                z.append(o.pop())
            ans.append(z[-1])
        else:
            if len(z) == 0:
                o.append(newPos)
            else:
                o.append(z.pop())
            ans.append(o[-1])
    print(len(z)+len(o))
    print(*ans)


def main():
    # Take input Here and Call solution function
    for _ in range(get_int()):
        n = get_int()
        s = get_string()
        Solution(s, n)


# calling main Function
if __name__ == '__main__':
    main()