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()
for _ in xrange(0, T):

    kingdoms = []

    N = input()
    for _ in xrange(0, N):

        L, R = map(int, raw_input().split())
        kingdoms.append((R, L))

    kingdoms = sorted(kingdoms)

    number_of_bombs_required = 0
    bomb_position = -1

    for r, l in kingdoms:
        if l > bomb_position:
            number_of_bombs_required += 1
            bomb_position = r

    print(number_of_bombs_required)