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 = '"""\n                            pppppppppppppppppppp\n                         ppppp  ppppppppppppppppppp\n                      ppppppp    ppppppppppppppppppppp\n                      pppppppp  pppppppppppppppppppppp\n                      pppppppppppppppppppppppppppppppp\n                              pppppppppppppppppppppppp\n       ppppppppppppppppppppppppppppppppppppppppppppppp  pppppppppppppppppppp\n      pppppppppppppppppppppppppppppppppppppppppppppppp  ppppppppppppppppppppp\n     ppppppppppppppppppppppppppppppppppppppppppppppppp  pppppppppppppppppppppp\n    ppppppppppppppppppppppppppppppppppppppppppppppp    pppppppppppppppppppppppp\n   pppppppppppppppppppppppppppppppppppppppppppppp     pppppppppppppppppppppppppp\n  ppppppppppppppppppppppppppppppppppppppppppppp      pppppppppppppppppppppppppppp\n  pppppppppppppppppppppppppppppppp               pppppppppppppppppppppppppppppppp\n  pppppppppppppppppppppppppppp     pppppppppppppppppppppppppppppppppppppppppppppp\n  ppppppppppppppppppppppppppp    pppppppppppppppppppppppppppppppppppppppppppppppp\n    pppppppppppppppppppppppp  pppppppppppppppppppppppppppppppppppppppppppppppppp\n     ppppppppppppppppppppppp  ppppppppppppppppppppppppppppppppppppppppppppppppp\n      pppppppppppppppppppppp  ppppppppppppppppppppppppppppppppppppppppppppppp\n       ppppppppppppppppppppp  ppppppppppppppppppppppppppppppppppppppppppppp\n                              pppppppppppppppppppppppp\n                              pppppppppppppppppppppppppppppppp\n                              pppppppppppppppppppppp  pppppppp\n                              ppppppppppppppppppppp    ppppppp\n                                 ppppppppppppppppppp  ppppp\n                                    pppppppppppppppppppp\n"""\n\n\nimport sys\nfrom functools import lru_cache, cmp_to_key\nfrom heapq import merge, heapify, heappop, heappush, nsmallest\nfrom math import ceil, floor, gcd, fabs, factorial, fmod, sqrt, inf\nfrom collections import defaultdict as dd, deque, Counter as C\nfrom itertools import combinations as comb, permutations as perm\nfrom bisect import bisect_left as bl, bisect_right as br, bisect\nfrom time import perf_counter\nfrom fractions import Fraction\nfrom decimal import Decimal\n# sys.setrecursionlimit(pow(10, 6))\n# sys.stdin = open("input.txt", "r")\n# sys.stdout = open("output.txt", "w")\nmod = pow(10, 9) + 7\nmod2 = 998244353\ndef data(): return sys.stdin.readline().strip()\ndef out(var): sys.stdout.write(str(var)+"\\n")\ndef outa(*var, end="\\n"): sys.stdout.write(\' \'.join(map(str, var)) + end)\ndef l(): return list(sp())\ndef sl(): return list(ssp())\ndef sp(): return list(map(int, data().split()))\ndef ssp(): return list(map(str, data().split()))\ndef l1d(n, val=0): return [val for i in range(n)]\ndef l2d(n, m, val=0): return [l1d(n, val) for j in range(m)]\n\n\nfor _ in range(int(data())):\n    n = int(data())\n    a = l()\n    answer = []\n    s = set()\n    for i in a:\n        if i not in s:\n            answer.append(i)\n        s.add(i)\n    outa(*answer)\n'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 16593