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10
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10
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'''
# Read input from stdin and provide input before running code

name = raw_input('What is your name?\n')
print 'Hi, %s.' % name
'''
t=input()
for i in range(t):
	p=input()
	z=[]
	for j in range(p):
		k=raw_input()
		z.append(k)
	z=set(z)
	l=len(z)
	z=list(z)
	z.sort()
	for i in range(l):
		print z[i]