Problem: The length of the longest common prefix of two strings s = s_1 s_2 … s_n and t = t_1 t_2 … t_m is defined as the maximum integer k (0 ≤ k ≤ min(n,m)) such that s_1 s_2 … s_k equals t_1 t_2 … t_k.

Koa the Koala initially has n+1 strings s_1, s_2, ..., s_{n+1}.

For each i (1 ≤ i ≤ n) she calculated a_i — the length of the longest common prefix of s_i and s_{i+1}.

Several days later Koa found these numbers, but she couldn't remember the strings.

So Koa would like to find some strings s_1, s_2, ..., s_{n+1} which would have generated numbers a_1, a_2, ..., a_n. Can you help her?

If there are many answers print any. We can show that answer always exists for the given constraints. 

Input

Each test contains multiple test cases. The first line contains t (1 ≤ t ≤ 100) — the number of test cases. Description of the test cases follows.

The first line of each test case contains a single integer n (1 ≤ n ≤ 100) — the number of elements in the list a.

The second line of each test case contains n integers a_1, a_2, …, a_n (0 ≤ a_i ≤ 50) — the elements of a.

It is guaranteed that the sum of n over all test cases does not exceed 100.

Output

For each test case:

Output n+1 lines. In the i-th line print string s_i (1 ≤ |s_i| ≤ 200), consisting of lowercase Latin letters. Length of the longest common prefix of strings s_i and s_{i+1} has to be equal to a_i.

If there are many answers print any. We can show that answer always exists for the given constraints.

Example

Input


4
4
1 2 4 2
2
5 3
3
1 3 1
3
0 0 0


Output


aeren
ari
arousal
around
ari
monogon
monogamy
monthly
kevinvu
kuroni
kurioni
korone
anton
loves
adhoc
problems

Note

In the 1-st test case one of the possible answers is s = [aeren, ari, arousal, around, ari].

Lengths of longest common prefixes are:

  * Between \color{red}{a}eren and \color{red}{a}ri → 1 
  * Between \color{red}{ar}i and \color{red}{ar}ousal → 2 
  * Between \color{red}{arou}sal and \color{red}{arou}nd → 4 
  * Between \color{red}{ar}ound and \color{red}{ar}i → 2 

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.PrintStream;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.util.function.Supplier;
import java.util.ArrayList;
import java.util.List;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author out_of_the_box
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        ACommonPrefixes solver = new ACommonPrefixes();
        int testCount = Integer.parseInt(in.next());
        for (int i = 1; i <= testCount; i++)
            solver.solve(i, in, out);
        out.close();
    }

    static class ACommonPrefixes {
        MiscUtility ut = new MiscUtility();

        public void solve(int testNumber, InputReader in, OutputWriter out) {
            int n = in.nextInt();
            int[] a = in.nextIntArray(n);
            List<String> ans = new ArrayList<>();
            if (n == 1) {
                StringBuilder bu = new StringBuilder();
                if (a[0] > 0) {
                    for (int i = 0; i < a[0]; i++) {
                        bu.append('a');
                    }
                    String temp = bu.toString();
                    out.println(temp);
                    out.println(temp);
                    return;
                } else {
                    out.println('a');
                    out.println('b');
                    return;
                }
            }
            StringBuilder builder = new StringBuilder();
            if (a[0] > 0) {
                for (int i = 0; i < a[0]; i++) {
                    builder.append('a');
                }
            } else {
                builder.append('b');
            }
            String prev = builder.toString();
            ans.add(prev);
            for (int i = 0; i < (n - 1); i++) {
                int ts = Math.max(1, Math.max(a[i], a[i + 1]));
                int pn = prev.length();
                StringBuilder b = new StringBuilder();
                for (int j = 0; j < a[i]; j++) {
                    b.append(prev.charAt(j));
                }
                int rem = ts - a[i];
                if (rem > 0) {
                    if (pn > a[i]) {
                        b.append(next(prev.charAt(a[i])));
                        rem--;
                        for (int j = 0; j < rem; j++) {
                            b.append('a');
                        }
                    } else {
                        for (int j = 0; j < rem; j++) {
                            b.append('a');
                        }
                    }
                }
                String sb = b.toString();
                ans.add(sb);
                prev = sb;
            }
            //Add last
            StringBuilder tb = new StringBuilder();
            if (a[n - 1] > 0) {
                for (int i = 0; i < a[n - 1]; i++) {
                    tb.append(prev.charAt(i));
                }
            } else {
                tb.append(next(prev.charAt(0)));
            }
            ans.add(tb.toString());

            ut.printDebug(testNumber, "testNumber", ans, "ans");
            for (String val : ans) {
                out.println(val);
            }
        }

        private char next(char ch) {
            if (ch == 'z') return 'a';
            return ((char) (ch + 1));
        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        public int nextInt() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public String nextString() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                if (Character.isValidCodePoint(c)) {
                    res.appendCodePoint(c);
                }
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public String next() {
            return nextString();
        }

        public int[] nextIntArray(int n) {
            int[] array = new int[n];
            for (int i = 0; i < n; ++i) array[i] = nextInt();
            return array;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }

    static class MiscUtility {
        public boolean debug;

        public MiscUtility() {
            debug = System.getProperty("ONLINE_JUDGE") == null;
        }

        public MiscUtility(boolean debug) {
            this.debug = debug;
        }

        public void printDebug(Object... objects) {
            if (debug) {
                boolean isName = false;
                Object prev = null;
                for (Object object : objects) {
                    if (isName) {
                        System.out.print(String.format("[%s: %s] ", object, prev.toString()));
                    } else {
                        prev = (object instanceof Supplier) ? (((Supplier) object).get()) : object;
                    }
                    isName = !isName;
                }
                System.out.println();
            }
        }

    }

    static class OutputWriter {
        private final PrintWriter writer;

        public OutputWriter(OutputStream outputStream) {
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
        }

        public OutputWriter(Writer writer) {
            this.writer = new PrintWriter(writer);
        }

        public void print(Object... objects) {
            for (int i = 0; i < objects.length; i++) {
                if (i != 0) {
                    writer.print(' ');
                }
                writer.print(objects[i]);
            }
        }

        public void println(Object... objects) {
            print(objects);
            writer.println();
        }

        public void println(char i) {
            writer.println(i);
        }

        public void close() {
            writer.close();
        }

    }
}