Codeforces Round 603 (Div. 2)
B
PIN Codes
Codeforces
1400
原题
← AC →
翻译中…

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.

翻译中…

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

翻译中…

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.

翻译中…

Formally, in one step, Polycarp picks $i$-th card ($1 \le i \le n$), 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.

翻译中…

Polycarp quickly solved this problem. Can you solve it?

翻译中…

Input

翻译中…

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

翻译中…

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

翻译中…

Output

翻译中…

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

翻译中…

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.

翻译中…

样例

Input #1
3
2
1234
0600
2
1337
1337
4
3139
3139
3139
3139
Output #1
0
1234
0600
1
1337
1237
3
3139
3138
3939
6139
InputCopy OutputCopy
题目信息
题号
1263B
时间限制
1 s
内存限制
256 MB
标签
贪心
模拟

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。