N one dimensional kingdoms are represented as intervals of the form [ai , bi] on the real line.
A kingdom of the form [L, R] can be destroyed completely by placing a bomb at a point x on the real line if L
≤ x ≤ R.


Your task is to determine minimum number of bombs required to destroy all the one dimensional kingdoms.

Input


First line of the input contains T denoting number of test cases.


For each test case, first line contains N denoting the number of one dimensional kingdoms.


For each next N lines, each line contains two space separated integers ai and bi.



Output
For each test case , output an integer denoting the minimum  number of bombs required.

Constraints
Example
Input:
1
3
1 3
2 5
6 9

Output:
2

Explanation
There are three kingdoms [1,3] ,[2,5] and [6,9]. You will need at least 2 bombs
to destroy the kingdoms. In one of the possible solutions, you can place two bombs at x = 2 and x = 6 .
t=input()
def lsort(l,n):              #therefore total order=O(n+2001) :)
	c=[0 for x in range(2001)]         #O(2001)
	for x in l:c[x[0]]+=1		#O(n)
	for i in range(1,2001):c[i]+=c[i-1]		#O(2001)
	b=[None for x in range(n)]	#O(n)
	for i in range(n):		#O(n)
		b[c[l[i][0]]-1]=l[i]
		c[l[i][0]]-=1
	return b
for qq in range(t):
	n=input()
	l=[]
	for qqq in range(n):l.append(map(int,raw_input().split()))
	l=lsort(l,n)
	ans=1
	state=l[0]
	#print l
	for x in range(n):
			if l[x][0]<=state[1]:
				state=(l[x][0],min(state[1],l[x][1]))
			else:
				state=l[x]
				ans+=1
	print ans