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 .
from operator import itemgetter
def ONEKING():
	t = int(raw_input())
	while t:
		n = int(raw_input()); L = []
		for i in range(n):
			s = raw_input().split(); x = [int(i) for i in s];
			L.append(tuple(x))
		L = sorted(L,key=itemgetter(1)); temp = [L[0]]; f = L[0][1]
		for i in range(1,len(L)):
			if L[i][0] > f: temp.append(L[i]); f = L[i][1] 
		print len(temp); t-=1
if __name__ == '__main__': ONEKING()