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=int(raw_input())
for i in xrange(t):
    dicti={}
    one=[]
    two=[]
    n=int(raw_input())
    for j in xrange(n):
        z=raw_input().split()
        a=int(z[0])
        b=int(z[1])
        one.append(a)
        two.append(b)
    #print one,two
    two, one = (list(x) for x in zip(*sorted(zip(two, one))))
    #print one,two
    maxi=-1
    ans=0
    for j in xrange(n):
        if one[j]>maxi:
            #print one[j],two[j]
            maxi=two[j]
            ans+=1

    print ans