Today Oz is playing a new game. He has an array arr[] of N distinct integers . In each turn he is will follow two actions - 
1) He select a random number from arr[]. Say value of this element is X.
2) He will remove X from arr[]. if X-1 is present in arr[] then he will remove it. if X+1 is present in arr[] then he will remove it.
Oz will make turns until arr[] becomes empty. Oz loves this game so he wants to make maximum number of possible turns. Help Oz to make maximum number of possible turns. 

Input :
The first line contains the number of test cases - T . Each test case consist of two lines. First line will contain a integer N - number of elements in arr[]. Second line will contain N space separated integers.

Output :
For each test case output maximum number of possible turns that Oz can make.

Constraints :
1 ≤ T ≤ 100
1 ≤ N ≤ 100
1 ≤ each element of arr[]  ≤ 1000

SAMPLE INPUT
1
6
291 292 295 297 298 299

SAMPLE OUTPUT
4

Explanation

One of the possible way to make 4 turns is by choosing the following elements in each turn: 297, 299, 295, 292.
from math import ceil

def getCnt(n):
	
	return int(round(float(n)/float(2)))
	
for t in xrange(input()):
	L =input()
	cnt = 0
	
	ar = sorted(map(int,raw_input().split(' ')))
	
	#print 'ar', ar
	if not ar :
		continue
	elif L == 1:
		print 1
		continue
	
	
	i = 1
	seq_len  = 1
	while i < L:
		#print i,ar[i-1],ar[i]
		if ar[i] == ar[i-1]+1: 
			seq_len += 1
		else :
			#print seq_len,'adding',getCnt(seq_len)
			cnt += getCnt(seq_len)
			seq_len = 1
			
		i+=1
	if i == L :
		#print 'seq_len',seq_len,getCnt(seq_len)
		cnt += getCnt(seq_len)
		
	print cnt