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 JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.FilterInputStream;
import java.io.BufferedInputStream;
import java.util.HashMap;
import java.util.ArrayList;
import java.io.InputStream;

/**
 * @author khokharnikunj8
 */

public class Main {
    public static void main(String[] args) {
        new Thread(null, new Runnable() {
            public void run() {
                new Main().solve();
            }
        }, "1", 1 << 26).start();
    }

    void solve() {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        ScanReader in = new ScanReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        BPINCodes solver = new BPINCodes();
        int testCount = in.scanInt();
        for (int i = 1; i <= testCount; i++)
            solver.solve(i, in, out);
        out.close();
    }

    static class BPINCodes {
        public void solve(int testNumber, ScanReader in, PrintWriter out) {
            int n = in.scanInt();
            HashMap<String, Integer> set = new HashMap<>();
            ArrayList<String> ans = new ArrayList<>();
            int answer = 0;
            String[] s = new String[n];
            for (int i = 0; i < n; i++) {
                s[i] = in.scanString();
                set.put(s[i], set.getOrDefault(s[i], 0) + 1);
            }

            for (int i = 0; i < n; i++) {
                if (set.getOrDefault(s[i], 0) <= 1) {
                    ans.add(s[i]);
                    continue;
                }
                int as = ans.size();
                out:
                for (int j = 0; j < 4; j++) {
                    for (int digit = 0; digit <= 9; digit++) {
                        String newS = "";
                        if (j != 0) newS = s[i].substring(0, j);
                        newS += digit;
                        if (j != 3) newS += s[i].substring(j + 1, 4);
                        if (set.getOrDefault(newS, 0) == 0) {
                            set.put(s[i], set.getOrDefault(s[i], 0) - 1);
                            set.put(newS, 1);
                            ans.add(newS);
                            answer++;
                            break out;
                        }
                    }
                }
                if (as == ans.size()) throw new RuntimeException();
            }
            out.println(answer);
            for (String temp : ans) {
                out.println(temp);
            }
        }

    }

    static class ScanReader {
        private byte[] buf = new byte[4 * 1024];
        private int index;
        private BufferedInputStream in;
        private int total;

        public ScanReader(InputStream inputStream) {
            in = new BufferedInputStream(inputStream);
        }

        private int scan() {
            if (index >= total) {
                index = 0;
                try {
                    total = in.read(buf);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                if (total <= 0) return -1;
            }
            return buf[index++];
        }

        public int scanInt() {
            int integer = 0;
            int n = scan();
            while (isWhiteSpace(n)) n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n)) {
                if (n >= '0' && n <= '9') {
                    integer *= 10;
                    integer += n - '0';
                    n = scan();
                }
            }
            return neg * integer;
        }

        public String scanString() {
            int c = scan();
            if (c == -1) return null;
            while (isWhiteSpace(c)) c = scan();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = scan();
            } while (!isWhiteSpace(c));
            return res.toString();
        }

        private boolean isWhiteSpace(int n) {
            if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1) return true;
            else return false;
        }

    }
}