new_contents: # http://www.codechef.com/DEC14/problems/CAPPLE
  
  def pluck(trees):
  
  	# find the biggest and the second biggest number in the list
  	maximum = max(trees)
  	second_max = max( map(lambda x: -1 if x == maximum else x, trees) )
  
  	if maximum == second_max:
  		return [0]*len(trees)
  	else:
  		diff = maximum - second_max
  		return map(lambda x: x - diff if x == maximum else x, trees)
  
  def time(trees):
  	counter = 0
  	while not all(i == 0 for i in trees):
  		trees = pluck(trees)
  		counter += 1
  	return counter - 1
  
  '''print time(range(1,1000))'''
  inputs = int(raw_input())
  while inputs:
  	length = int(raw_input())
  	trees = map(int, raw_input().split())
  	print time(trees)
  	inputs -= 1
subject: Write solution to Chef and Apples problem.