A permutation of length $n$ is a sequence of integers from $1$ to $n$ of length $n$ containing each number exactly once. For example, $[1]$, $[4, 3, 5, 1, 2]$, $[3, 2, 1]$ are permutations, and $[1, 1]$, $[0, 1]$, $[2, 2, 1, 4]$ are not.

There was a permutation $p[1 \dots n]$. It was merged with itself. In other words, let's take two instances of $p$ and insert elements of the second $p$ into the first maintaining relative order of elements. The result is a sequence of the length $2n$.

For example, if $p=[3, 1, 2]$ some possible results are: $[3, 1, 2, 3, 1, 2]$, $[3, 3, 1, 1, 2, 2]$, $[3, 1, 3, 1, 2, 2]$. The following sequences are not possible results of a merging: $[1, 3, 2, 1, 2, 3$], [$3, 1, 2, 3, 2, 1]$, $[3, 3, 1, 2, 2, 1]$.

For example, if $p=[2, 1]$ the possible results are: $[2, 2, 1, 1]$, $[2, 1, 2, 1]$. The following sequences are not possible results of a merging: $[1, 1, 2, 2$], [$2, 1, 1, 2]$, $[1, 2, 2, 1]$.

Your task is to restore the permutation $p$ by the given resulting sequence $a$. It is guaranteed that the answer exists and is unique.

You have to answer $t$ independent test cases.


-----Input-----

The first line of the input contains one integer $t$ ($1 \le t \le 400$) — the number of test cases. Then $t$ test cases follow.

The first line of the test case contains one integer $n$ ($1 \le n \le 50$) — the length of permutation. The second line of the test case contains $2n$ integers $a_1, a_2, \dots, a_{2n}$ ($1 \le a_i \le n$), where $a_i$ is the $i$-th element of $a$. It is guaranteed that the array $a$ represents the result of merging of some permutation $p$ with the same permutation $p$.


-----Output-----

For each test case, print the answer: $n$ integers $p_1, p_2, \dots, p_n$ ($1 \le p_i \le n$), representing the initial permutation. It is guaranteed that the answer exists and is unique.


-----Example-----
Input
5
2
1 1 2 2
4
1 3 1 4 3 4 2 2
5
1 2 1 2 3 4 3 5 4 5
3
1 2 3 1 2 3
4
2 3 2 4 1 3 4 1

Output
1 2 
1 3 4 2 
1 2 3 4 5 
1 2 3 
2 3 4 1

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

ns = {"__name__": "__main__"}
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = "from bisect import bisect_left as bl\nfrom bisect import bisect_right as br\nfrom heapq import heappush,heappop,heapify\nimport math\nfrom collections import *\nfrom functools import reduce,cmp_to_key\nimport sys\ninput = sys.stdin.readline\nM = mod = 998244353\ndef factors(n):return sorted(set(reduce(list.__add__, ([i, n//i] for i in range(1, int(n**0.5) + 1) if n % i == 0))))\ndef inv_mod(n):return pow(n, mod - 2, mod)\n \ndef li():return [int(i) for i in input().rstrip('\\n').split()]\ndef st():return input().rstrip('\\n')\ndef val():return int(input().rstrip('\\n'))\ndef li2():return [i for i in input().rstrip('\\n')]\ndef li3():return [int(i) for i in input().rstrip('\\n')]\n\nfor _ in range(val()):\n    n = val()\n    l = li()\n    visited = {}\n    ans = []\n    for i in l:\n        if i not in visited:\n            ans.append(i)\n        visited[i] = 1\n    print(*ans)"
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 14985