5
10
bb
bb
ab
aa
bb
bb
ba
aa
bb
ab
10
bb
ab
ba
ab
ba
ba
ab
ba
ba
ba
10
aa
ba
ba
ba
bb
ab
ab
aa
bb
bb
10
ab
ab
bb
bb
ab
ba
aa
ba
ab
aa
10
ba
bb
bb
bb
aa
ba
ba
ba
bb
bb
aa
ab
ba
bb
ab
ba
bb
aa
ab
ba
bb
aa
ab
ba
bb
aa
ba
bb

try:
	test = input()
	if test in range(1,11):
		for tests in range(test):
			numb = input()
			name = []
			for number in range(numb):
				name.append(raw_input())
			name = list(set(name))
			name.sort()
			print "\n".join(name)
	else:
		exit
except:
	exit