Problem: A PIN code is a string that consists of exactly 4 digits. Examples of possible PIN codes: 7013, 0000 and 0990. Please note that the PIN code can begin with any digit, even with 0.

Polycarp has n (2 ≤ n ≤ 10) bank cards, the PIN code of the i-th card is p_i.

Polycarp has recently read a recommendation that it is better to set different PIN codes on different cards. Thus he wants to change the minimal number of digits in the PIN codes of his cards so that all n codes would become different.

Formally, in one step, Polycarp picks i-th card (1 ≤ i ≤ n), then in its PIN code p_i selects one position (from 1 to 4), and changes the digit in this position to any other. He needs to change the minimum number of digits so that all PIN codes become different.

Polycarp quickly solved this problem. Can you solve it?

Input

The first line contains integer t (1 ≤ t ≤ 100) — the number of test cases in the input. Then test cases follow.

The first line of each of t test sets contains a single integer n (2 ≤ n ≤ 10) — the number of Polycarp's bank cards. The next n lines contain the PIN codes p_1, p_2, ..., p_n — one per line. The length of each of them is 4. All PIN codes consist of digits only.

Output

Print the answers to t test sets. The answer to each set should consist of a n + 1 lines

In the first line print k — the least number of changes to make all PIN codes different. In the next n lines output the changed PIN codes in the order corresponding to their appearance in the input. If there are several optimal answers, print any of them.

Example

Input


3
2
1234
0600
2
1337
1337
4
3139
3139
3139
3139


Output


0
1234
0600
1
1337
1237
3
3139
3138
3939
6139

Solution (in PYTHON3):

Solution:
#from statistics import median
#import collections
#aa = collections.Counter(a) # list to list || .most_common(2)で最大の2個とりだせるお a[0][0]
# from math import gcd
# from itertools import combinations,permutations,accumulate, product # (string,3) 3回
# #from collections import deque
# from collections import deque,defaultdict,Counter
# import decimal
# import re
# import math
# import bisect
# import heapq
#
#
#
# pythonで無理なときは、pypyでやると正解するかも！！
#
#
# my_round_int = lambda x:np.round((x*2 + 1)//2)
# 四捨五入g
#
# インデックス系
# int min_y = max(0, i - 2), max_y = min(h - 1, i + 2);
# int min_x = max(0, j - 2), max_x = min(w - 1, j + 2);
#
#
# import sys
# sys.setrecursionlimit(10000000)
mod = 10**9 + 7
#mod = 9982443453
#mod = 998244353
INF = float('inf')
# from sys import stdin
# readline = stdin.readline
def readInts():
  return list(map(int,input().split()))
def readTuples():
    return tuple(map(int,input().split()))
def I():
    return int(input())
q = I()
from collections import Counter,defaultdict

for _ in range(q):
    n = I()
    S = [input() for _ in range(n)]
    dic = Counter(S)
    ans = 0
    next = defaultdict(int)
    for k,v in dic.items():
        next[k] = int(v)
        ans += v-1
    print(ans)
    RES = defaultdict(int)
    for idx in range(n):
        value = int(S[idx])
        if RES[value] == 0:
            print("%04d"%(value))
            RES[value] = 1
            dic[value] -= 1
            next[value] = value
        elif dic[S[idx]] >= 1:
            # print('raw',raw_number)2
            raw_number = next[value]
            for i in range(1,3):
                dived = raw_number // (10 ** i)
                MOD = dived % 10
                raw_number -= (10 ** i) * MOD
                for j in range(10):
                    raw_number += ((MOD + j + 1) % 10) * max(1,(10 ** i))
                    #print(raw_number,MOD,j,i)
                    if RES[raw_number] == 0 and dic[str(raw_number)] == 0:
                        print("%04d"%(raw_number))
                        RES[raw_number] = 1
                        next[value] = raw_number
                        dic[S[idx]]-= 1
                        break
                    raw_number -= ((MOD + j + 1) % 10) * max(1,(10 ** i))
                else:
                    continue
                break