Problem: A bitstring is a string that contains only the characters 0 and 1.

Koyomi Kanou is working hard towards her dream of becoming a writer. To practice, she decided to participate in the Binary Novel Writing Contest. The writing prompt for the contest consists of three bitstrings of length 2n. A valid novel for the contest is a bitstring of length at most 3n that contains at least two of the three given strings as subsequences.

Koyomi has just received the three prompt strings from the contest organizers. Help her write a valid novel for the contest.

A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero) characters.

Input

The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases.

The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5).

Each of the following three lines contains a bitstring of length 2n. It is guaranteed that these three strings are pairwise distinct.

It is guaranteed that the sum of n across all test cases does not exceed 10^5.

Output

For each test case, print a single line containing a bitstring of length at most 3n that has at least two of the given bitstrings as subsequences.

It can be proven that under the constraints of the problem, such a bitstring always exists.

If there are multiple possible answers, you may output any of them.

Example

Input


2
1
00
11
01
3
011001
111010
010001


Output


010
011001010

Note

In the first test case, the bitstrings 00 and 01 are subsequences of the output string: 010 and 010. Note that 11 is not a subsequence of the output string, but this is not required.

In the second test case all three input strings are subsequences of the output string: 011001010, 011001010 and 011001010.

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;

public final class Solution {


    static PrintWriter out = new PrintWriter(System.out);
    static FastReader in = new FastReader();
    static long mod = (long) 1e9 + 7;
    static Pair[] moves = new Pair[]{new Pair(-1, 0), new Pair(1, 0), new Pair(0, -1), new Pair(0, 1)};

    public static void main(String[] args) {
        int t = i();
        out:
        while (t-- > 0) {
            int n = i();
            String s1 = s();
            String s2 = s();
            String s3 = s();

            int o1 = 0;
            int o2 = 0;
            int o3 = 0;
            for (int i = 0; i < s1.length(); i++) {
                o1 += s1.charAt(i) - '0';
                o2 += s2.charAt(i) - '0';
                o3 += s3.charAt(i) - '0';
            }
            if (o1 >= n && o2 >= n) {
                out.println(ans(n, s1, s2, '1'));
            } else if (o1 >= n && o3 >= n) {
                out.println(ans(n, s1, s3, '1'));
            } else if (o2 >= n && o3 >= n) {
                out.println(ans(n, s2, s3, '1'));
            } else if (o1 <= n && o2 <= n) {
                out.println(ans(n, s1, s2, '0'));
            } else if (o1 <= n && o3 <= n) {
                out.println(ans(n, s1, s3, '0'));
            } else if (o2 <= n && o3 <= n) {
                out.println(ans(n, s2, s3, '0'));
            }
        }
        out.flush();
    }

    public static String ans(int n, String s1, String s2, char c) {
        StringBuilder sb = new StringBuilder();
        int comon = 0;
        int i = 0;
        int j = 0;
        while (comon < n) {
            if (s1.charAt(i) != c) {
                sb.append(s1.charAt(i++));
            } else if (s2.charAt(j) != c) {
                sb.append(s2.charAt(j++));
            } else {
                sb.append(c);
                i++;
                j++;
                comon++;
            }
        }
        while (i < 2 * n) {
            sb.append(s1.charAt(i++));
        }
        while (j < 2 * n) {
            sb.append(s2.charAt(j++));
        }
        return sb.toString();
    }

    public static long calc(int type, long X, long K) {
        if (type == 1) {
            return (X + 99999) / 100000 + K;
        } else {
            return (K * X + 99999) / 100000;
        }
    }

    static int sd(long i) {
        int d = 0;
        while (i > 0) {
            d += i % 10;
            i = i / 10;
        }
        return d;
    }


    static int lower(long A[], long x) {
        int l = -1, r = A.length;
        while (r - l > 1) {
            int m = (l + r) / 2;
            if (A[m] >= x) {
                r = m;
            } else {
                l = m;
            }
        }
        return r;
    }

    static int upper(long A[], long x) {
        int l = -1, r = A.length;
        while (r - l > 1) {
            int m = (l + r) / 2;
            if (A[m] <= x) {
                l = m;
            } else {
                r = m;
            }
        }
        return l;
    }

    static void swap(int A[], int a, int b) {
        int t = A[a];
        A[a] = A[b];
        A[b] = t;
    }

    static int lowerBound(int A[], int low, int high, int x) {
        if (low > high) {
            if (x >= A[high]) {
                return A[high];
            }
        }

        int mid = (low + high) / 2;

        if (A[mid] == x) {
            return A[mid];
        }

        if (mid > 0 && A[mid - 1] <= x && x < A[mid]) {
            return A[mid - 1];
        }

        if (x < A[mid]) {
            return lowerBound(A, low, mid - 1, x);
        }

        return lowerBound(A, mid + 1, high, x);
    }


    static long pow(long a, long b) {
        long pow = 1;
        long x = a;
        while (b != 0) {
            if ((b & 1) != 0) {
                pow = (pow * x) % mod;
            }
            x = (x * x) % mod;
            b /= 2;
        }
        return pow;
    }

    static boolean isPrime(long N) {
        if (N <= 1) {
            return false;
        }
        if (N <= 3) {
            return true;
        }
        if (N % 2 == 0 || N % 3 == 0) {
            return false;
        }
        for (int i = 5; i * i <= N; i = i + 6) {
            if (N % i == 0 || N % (i + 2) == 0) {
                return false;
            }
        }
        return true;
    }

    static void print(char A[]) {
        for (char c : A) {
            out.print(c);
        }
        out.println();
    }

    static void print(boolean A[]) {
        for (boolean c : A) {
            out.print(c + " ");
        }
        out.println();
    }

    static void print(int A[]) {
        for (int c : A) {
            out.print(c + " ");
        }
        out.println();
    }

    static void print(long A[]) {
        for (long i : A) {
            out.print(i + " ");
        }
        out.println();

    }

    static void print(ArrayList<Integer> A) {
        for (int a : A) {
            out.print(a + " ");
        }
    }

    static int i() {
        return in.nextInt();
    }

    static long l() {
        return in.nextLong();
    }

    static String s() {
        return in.nextLine();
    }

    static int[] input(int N) {
        int A[] = new int[N];
        for (int i = 0; i < N; i++) {
            A[i] = in.nextInt();
        }
        return A;
    }

    static long[] inputLong(int N) {
        long A[] = new long[N];
        for (int i = 0; i < A.length; i++) {
            A[i] = in.nextLong();
        }
        return A;
    }

    static int GCD(int a, int b) {
        if (b == 0) {
            return a;
        } else {
            return GCD(b, a % b);
        }
    }

    static long GCD(long a, long b) {
        if (b == 0) {
            return a;
        } else {
            return GCD(b, a % b);
        }
    }

}

class SegmentTree {

    long[] t;

    public SegmentTree(int n) {
        t = new long[n + n];
        Arrays.fill(t, Long.MIN_VALUE);
    }

    public long get(int i) {
        return t[i + t.length / 2];
    }

    public void add(int i, long value) {
        i += t.length / 2;
        t[i] = value;
        for (; i > 1; i >>= 1) {
            t[i >> 1] = Math.max(t[i], t[i ^ 1]);
        }
    }

    // max[a, b]
    public long max(int a, int b) {
        long res = Long.MIN_VALUE;
        for (a += t.length / 2, b += t.length / 2; a <= b; a = (a + 1) >> 1, b = (b - 1) >> 1) {
            if ((a & 1) != 0) {
                res = Math.max(res, t[a]);
            }
            if ((b & 1) == 0) {
                res = Math.max(res, t[b]);
            }
        }
        return res;
    }
}

class Pair {

    int i, j;

    Pair(int i, int j) {
        this.i = i;
        this.j = j;
    }
}

class FastReader {

    BufferedReader br;
    StringTokenizer st;

    public FastReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    String nextLine() {
        String str = "";
        try {
            str = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return str;
    }


}